Up to 5,000 flights could have been affected by the end of Thursday. Planes have been grounded in the UK, Ireland, the Netherlands, Belgium, Denmark, Norway, Sweden and Finland. France is also preparing to close its main airports. Eurocontrol, which covers 38 nations across Europe, said the ash ejected by the volcano underneath the Eyjafjallajoekull glacier in Iceland would continue to move in a south-easterly direction.

Experts have warned that the tiny particles of rock, glass and sand contained in the ash cloud could be sufficient to jam aircraft engines. Mr Flynn, Eurocontrol's assistant head of operations, said the extent of the disruption was "greater than we've ever seen before in the EU" and warned that the problem could persist for a further 48 hours.

"The meteorological situation is such that the volcanic ash is progressing very slowly eastwards but there is not a lot of wind... so it is very slow and very dense," he told the Reuters news agency.

The restrictions silenced Heathrow airport, the world's second busiest, and stranded tens of thousands of passengers around the world. Norway, Denmark, Sweden, Belgium and the Netherlands all later shut down their airspace entirely, while there was also major disruption in Finland, France, Germany and Spain.

"We will review further Met Office information, and at 0230 BST tomorrow we will advise the arrangements that will be in place through to 1800 BST tomorrow. However, be aware that the situation cannot be said to be improving with any certainty as the forecast affected area appears to be closing in from east to west. We continue to work closely with airports, airlines, and the rest of Europe to understand and mitigate the implications of the volcanic eruption."

The statement from the Israeli prime minister's anti-terror office took the unusual step of calling on families of Israelis visiting the Sinai to establish contact with them.

The commander of the anti-terror office, Brigadier General Nitzan Nuriel, acknowledged that there had been rumors that Israelis have been kidnapped in the Sinai. "We don't work according to rumors," he Israel TV. "We work according to firm intelligence." He said it would "take some time" to disprove the rumors, which circulated all day Tuesday.

"It is very possible that at this moment, there is a terror cell that has the intention and has a plan in operation to kidnap an Israeli and bring him to Gaza," he said. Palestinian militants in Gaza have been holding an Israeli soldier captive for more than three years. In unusually strong wording, the Israeli anti-terror office called "on all Israelis residing in Sinai to leave immediately and return home. Families of Israelis residing in Sinai are asked to contact them and update them on the travel warning."

And their alleged plan ended in disaster when the Polish pilots made one final and disastrous attempt to land, killing Mr Kaczynski, his wife, and 94 others on board the plane. 'One version of events says that the plane approached the airport four times, because every time the Russians refused it permission to land - they wanted to send the plane with the president to an airport in Moscow or Minsk,' Mr Gorski claimed in an interview published in the newspaper Nasz Dziennik.

'They came up with some dubious reasons: that there was fog over the airport, and that the navigation system didn't work as it was under renovation, and that airport had a short landing strip.' The claims were made as shocking new details emerged of the final minutes of the flight before it crashed into a Russian forest on Saturday morning. One of the Russian air traffic controllers involved in the tragedy said he believes the Polish air force pilot Arkadiusz Protasiuk, 36, was under severe pressure 'to land at any cost' so that the president would not miss the commemoration of the death of 22,000 Poles slaughtered by Stalin.

But he claims there were also serious language problems between the control tower at the military airport near Smolensk and the crew as the aircraft began its descent, and final approach, 'without our permission'. The crew failed to report to the ground their altitude readings, said Colonel Anatoly Muraviev, a former pilot. He believes the captain 'was desperate to land because of the high ranking passengers he was carrying. It killed both the crew and the passengers.'

It was known that Mr Kaczynski once fired a flight crew when they refused to land at Tbilisi - and flew to another airport, he said. 'Now try to imagine yourself in chief pilot's shoes. Fear, false shame, thinking that going to another airport is a disgrace - all this led to the fact that the crew died and killed all the others. I am a former pilot myself, I understand all this very well.'

Cardinal Tarcisio Bertone had said homosexuality, not celibacy, lay behind the child sex abuse scandals. The cardinal, the Vatican's foreign minister, was speaking in Chile, where his comments were also condemned. Cardinal Bertone was attempting to defuse the scandals currently afflicting the Catholic Church, which are largely cases of priests molesting children, mainly boys, the BBC's David Willey reports from Rome. He added that some "surprising" initiatives regarding the sex abuse scandal would soon be revealed but did not elaborate.

Visiting the Chilean capital Santiago on Monday, Cardinal Bertone told a news conference: "Many psychologists, many psychiatrists have demonstrated that there is no relationship between celibacy and paedophilia but many others have demonstrated, I was told recently, that there is a relationship between homosexuality and paedophilia. That is true. I have the documents of the psychologists. That is the problem."

A Chilean communist MP, Hugo Gutierrez, told AFP news agency: "Celibacy does more damage to a human being than homosexuality, which is a freely made choice. I'm shocked by these words from a senior dignitary of the Church." Aurelio Mancuso, former president of a Italian gay rights association Arcigay, said: "The truth is that Bertone is clumsily trying to shift attention to homosexuality and away from the focus on new crimes against children that emerge every day."

Chinese TV showed wrecked buildings and people scrabbling through debris, as the government began a rescue misssion. Yushu is hundreds of miles from an airport, and it is thought rescue crews may take time to reach the quake zone. "Soldiers have been dispatched to save the people buried in the collapsed houses," local official Huang Limin was quoted as saying by China's state news agency Xinhua.

The region, which is home to ethnic Mongolians and Tibetan farmers and herdsmen, is dotted with coal, tin, lead and copper mines. China's Sichuan province, which neighbours Qinghai, suffered a huge earthquake in 2008, when thousands of schoolchildren were among the 87,000 people killed or missing. Five million people also lost their homes, and officials estimated rebuilding work would take at least three years.

The Niagara County Community College, a state university in New York, lecturer said due to the high amount of sightings every year, it should follow that students should be able to investigate phenomenon. "(A sighting) happens to millions of people (around the world)," he said. "It's about time we looked into this as a worthy area of study. It's important that the whole subject be brought out in the open and investigated."

Prof Haseley, who is also head of the Western New York Mutual UFO Network, an organisation that is focused on UFO research, said there were up to 50 UFO sightings are reported every month across region. He said the group investigated the sightings in a "scientific manner" using field investigation, radar, astronomy and meteorology. "To say we are UFO believers basically implies we are taking this on faith, and that's not the case. There's plenty of evidence," he said.

He dismissed the inevitable suggestions from skeptics that such study would be waste of time.

Some nights Albert Snyder wakes up at 3 am. Other nights he doesn't sleep at all, tormented by thoughts of the hateful signs carried by a fundamentalist church outside his Marine son's funeral.

"Thank God for Dead Soldiers."

"You're Going to Hell."

"Semper Fi Fags."

Most mourners try to ignore the taunts. But Snyder couldn't let it go. He became the first to sue the church to halt the demonstrations, and he's pursued the group farther than anyone else. His tireless efforts have drawn support from across the country, including a wave of donations after he was ordered to pay the church's court costs - a $16,500 judgment that the congregation plans to use for more protests.

Lance Corporal Matthew A Snyder, 20, was not gay. But for the Westboro church, any dead soldier is fair game. Pastor Fred Phelps oversees a congregation of 70 to 80 members - mostly his children and grandchildren. They consider themselves prophets, and they insist the nation is doomed.

Israeli diplomats attribute Mr Netanyahu's last-minute cancellation to Turkish and Egyptian plans to discuss Israel's nuclear arsenal. But his absence from an event intended to show US allies and partners rallying around the American president's agenda was, at the very least, deeply symbolic. The US-Israeli alliance, for decades the cornerstone of Middle East power politics, is in rocky shape. The Obama administration is angry about Israeli settlements in occupied East Jerusalem.

Mr Netanyahu's government is recoiling at what it depicts as Mr Obama's unreasonable demands. The tension between the two sides has become a story of personal snubs and policy differences even as the US and Israel profess their devotion to each other. As George Mitchell, Washington's Middle East envoy, prepares to return to the region, US officials are considering eventually issuing outlines of their own for an Israeli-Palestinian deal - a turn of events Israel is desperate to avoid.

One thing is clear: even as the diplomatic tensions mount, no one in Washington is questioning the American commitment to Israel's security, a pledge described by Mrs Clinton as "rock-solid, unwavering, enduring and for ever". She boasted in her Aipac speech that Washington was increasing the $3 billion military assistance the US delivers to Israel each year. Nor does the Obama administration see much scope in reducing other subsidies to Israel. All the same, some officials are looking at one possible source of pressure: eventually issuing US "parameters" or guidelines for a peace deal.

The Obama administration is, in other words, shaping a policy more nuanced than its predecessors': it seeks to blend a cast-iron commitment to Israel's security with a much more critical stance on settlement building and the peace process. As Iran continues its progress towards nuclear capability, it is a distinction that seems unlikely to disappear. For Mr Netanyahu and his government, uncomfortable times lie ahead.

But he said the so-called P5 - the five permanent members on the Security Council - should press Israel on its refusal to join the nuclear Non-Proliferation Treaty (NPT). "Let's also try to convince the P5 to bring Israel onboard. You see, you have possibly today two emerging threats" in the Middle East, Gheit told the "PBS Newshour" on US public television.

"We are eager that we do not have a nuclear Iran, as well as we do not want to see a nuclear Israel. We want a zone that is free of nuclear weapons - and it can be done," he said. Israel is widely believed to have nuclear weapons but maintains a policy of strategic ambiguity, refusing to confirm or deny its arsenal.

Iran is part of the NPT but Western powers believe it is in violation of the treaty and is pursuing nuclear weapons. The clerical regime insists it is only seeking the peaceful use of nuclear energy. Israeli Prime Minister Benjamin Netanyahu at the last minute pulled out of the Washington summit, reportedly out of concern that Arab states and Turkey would shift the focus to Israel and away from its arch-enemy Iran.

Analysts said the Dow's move above 11,000 could provide a psychological boost and perhaps draw more investors to the market. "There is a huge stockpile of cash on the sidelines earning virtually nothing," said Jack Ablin, chief investment officer at Harris Private Bank in Chicago. "Maybe this can help shake a few people into the market."

Stocks have been rising this year on growing expectations that the economy will shake off job market weakness and housing problems. A test of whether the Dow can hold the 11,000 mark will come in the next three weeks when companies report earnings. Investors also will want to see whether the government's next employment report, due in early May, shows that employers added jobs in April as they did during March.

On Monday, a loan agreement for Greece allowed US investors to focus on domestic economic and corporate news, including announcements of two big deals. Investors have been concerned that mounting debt in Greece and other European nations including Spain and Portugal would stunt a global recovery. "This is clearly a positive development that the EU is identifying and dealing with what has really been it's first real challenge," said Alan Gayle, senior investment strategist for RidgeWorth Investments.

Britain's FTSE 100 rose 0.1 percent, Germany's DAX index rose less than 0.1 percent, and France's CAC-40 slipped less than 0.1 percent. Japan's Nikkei stock average rose 0.4 percent.

Schmidt said he doesn't want 'to be treated as a stranger' when reading online, Politico reports. He envisions a future where technology for news editing could help tailor advertisements for individual readers. And he wants to be challenged through technology that 'directs readers' to a story with an 'opposing' view.

An odd suggestion from the CEO of a company long accused of offering little to no conservative-leaning links on its news page, while aggressively promoting left-leaning hubs. Schmidt said GOOGLE is working on new ways to push adverts and content for consumers, based on what stories they've read.

Meanwhile France's leader stressed his country could not give up its own nuclear weapons. The US welcomed a Ukrainian pledge to eliminate its stockpile of highly enriched uranium by 2012. The two-day summit is taking place without representatives of Iran and North Korea, neither of whom were invited by the US because of the disputes over their nuclear programmes. The head of the International Atomic Energy Agency, Ikia Amano, said that nuclear powers needed to do more to protect nuclear materials.

"The problem is that nuclear material and radioactive material are not well protected and member states need to better protect these materials against the theft or smuggling," he told the BBC. "On average every two days we receive one new information on an incident involving theft or smuggling of nuclear material." British Foreign Secretary David Miliband said that nuclear nations like Pakistan were vulnerable. "The message from this summit is that any country can be treated as a normal country on nuclear matters if it behaves like a normal country," he said.

Speaking in an interview before the summit opened, French President Nicolas Sarkozy said his country would not give up its nuclear weapons because to do so would be to jeopardise national security. "I cannot jeopardise the security and safety of my country," he told CBS News. "I have inherited the legacy of the efforts made by my predecessors to build up France as a nuclear power and I could not give up nuclear weapons if I wasn't sure the world was a stable and safe place."

Last week, the US and Russia signed a new Strategic Arms Reduction Treaty, reducing each country's deployed nuclear arsenal to 1,550 weapons. Mr Obama has also approved a new nuclear policy for the US, saying he plans to cut the nuclear arsenal, refrain from nuclear tests and not use nuclear weapons against countries that do not have them.

More than 1 million pounds and hundreds of hours of treatment time are being spent tackling conditions such as obesity, tooth decay, alcohol abuse and the problems caused by passive smoking. Steve Ryan, medical director at Alder Hey, said preventable conditions are also diverting vital resources away from more serious illnesses.

One of the areas most affected by preventable conditions is the dental department. More than half of the 1,000 dental operations carried out each year are on children under the age of six. Dental surgeon Sharon Lee said she sees a constant stream of toddlers: "It obviously upsets me immensely but we do have a job to do to look after the child." Between 500 to 1,000 children a year end up in hospital because they are exposed to their parents' smoking.

Obesity is also putting a strain on resources, with admissions linked to obesity in both adults and children in England up from 5,056 in 2007-08 to 8,085 for 2008-09. In Liverpool, the consultant who deals with children who are seriously obese is Mohammed Didi. He said he is seeing heavier children at a younger age: "It is maybe to do with their diet. With parents working quite often, the amount of time they spend watching television, how much time they spend outside being physically active and the type of foods they eat." He added that while he can give advice - it is what goes on at home that matters.

He said the very real prospect of a generation of British children dying before their parents is a sleeping giant. "I think that we've never been here before. We've never faced this epidemic. It didn't happen in history. There were cholera epidemics, measles epidemics, whooping cough epidemics... (this) is subtle. It is in the background. But it's massive."

Some 87 per cent of Latvia's debts are in euros or other foreign currencies, and are owed mainly to Swedish banks, while Hungary and Romania owe euro-debts mainly to Austrian banks. So their government borrowing by non-euro members has been to support exchange rates to pay these private-sector debts to foreign banks, not to finance a domestic budget deficit as in Greece.

All these debts are unpayably high because most of these countries are running deepening trade deficits and are sinking into depression. Now that real estate prices are plunging, trade deficits are no longer financed by an inflow of foreign-currency mortgage lending and property buyouts. There is no visible means of support to stabilize currencies (eg healthy economies).

For the past year these countries have supported their exchange rates by borrowing from the EU and IMF. The terms of this borrowing are politically unsustainable: sharp public sector budget cuts, higher tax rates on already over-taxed labor, and austerity plans that shrink economies and drive more labor to emigrate.

The most recent shot was fired on April 6 when Moody's downgraded Iceland's debt from stable to negative. "Moody's acknowledged that Iceland might still achieve a better deal in renewed negotiations, but said the current uncertainty was hurting the country's short-term economic and financial prospects." The fight is on. It should be an interesting decade.