Many clutched a razor wire fence, desperately searching the crowds on the other side for a familiar face as they tried to discover whether their loved ones were still alive and at liberty, or in another of the camps, where the overcrowded conditions and made worse by poor sanitation, inadequate food and severe water shortages.

The refugees are not allowed to leave the camps even if they are not suspected of being Tamil Tiger fighters. While the Colombo government has said that it will clear the camps during the course of the year, it is anxious not to allow separatist fighters to evade their reach by posing as civilians and simply walking free.

Bhuvaneswari, whose son and two daughters are missing, held photographs through the wire. “Nine members of my family are missing, please help me find them,” she said. “They’ve been missing since the mass exodus on April 20th. When the army entered the safe zone and cut the area in two, we were separated. We don’t know if they’ve been killed by the army or what.”

At “Zone Four”, a camp for recent arrivals, men stripped to the waist were washing themselves in an open drain. One man showed his camp ration card which recorded only two evening meals in six days, while another emaciated elderly man was so weak from an infection that he could not stand or speak and appeared close to death as he lay in a crowded tent.

Many said they had been shelled from their homes in the army’s ferocious advance across the north-east of the island, and they had been forced to flee more than a dozen times before reaching the so-called “no-fire zone”.

Thangaraja, 59, a carpenter, said that his family had moved 14 times since January as the Tigers retreated into the “no-fire zone” on the north-east coast. He said they had been shelled by the army, shot at by Tamil Tigers to stop them escaping, and lost several relatives in the cross-fire.

“My son and daughter-in-law, my brother-in-law, my cousin, all died in shelling attacks. We built bunkers and kept moving from one place to another. Shells were falling everywhere. Four people died in my family while I was there. We just left their bodies in the bunker and filled them in,” he said.

He wants to go back to his home “in freedom”, but his main concern is for other missing relatives. “Lots of my relatives have been injured but we don’t know where they are. We can’t go outside the camp to contact people,” he said.

An army spokesman said that up to 6,000 families had been reunited to date, and that they were working to bring separated families together.

But he added: “At the moment we don’t know how many families are separated or how many disappeared.”

One refugee said that thousands of fleeing civilians were separated from their families when they reached the army check-point, where they were pushed onto buses and taken to different hospitals and camps. Navamani, 43, from Vattuvagal in Mullaitivu district, said she had lost her three children, aged 16,18 and 21, in the chaos.

At Vavuniya’s Zone Two, a few miles down the road, a mother and daughter who had been separated for five months had finally found one another, but were not allowed to embrace.

Kandaswamy, 73, was weeping on one side of the razor-wire, and reaching out to her daughter, Laxmi, 45, who has been in detention since fleeing the final battle earlier this month. She needed all the comfort she could get – four of her five children had been killed in shelling, she said.

Facebook has sold a 1.96% stake for $200m (£126m) to a Russian internet firm, a move that values the social networking website at $10bn.

Facebook boss Mark Zuckerberg said he had been impressed by Digital Sky Technology’s (DST) “impressive growth and financial achievements”.

DST has investments in a number of internet firms across Russia and Eastern Europe.

US-based Facebook has more than 200 million global members.

‘Ongoing success’

Facebook said DST would not be represented on its board or hold special observer rights.

“This investment demonstrates Facebook’s ongoing success at creating a global network for people to share and connect,” added Mr Zuckerberg, Facebook’s chief executive.

“A number of firms approached us, but DST stood out because of the global perspective they bring.”

DST’s internet businesses account for more than 70% of all page views on Russian language websites.

It has investments in sites including Mail.ru, Forticom and vKontakte.

The deal comes two years after Facebook sold a 1.6% stake to Microsoft for $240m.

General Motors’ bondholders have rejected a key part of the carmaker’s restructuring plan, which makes it more likely to seek bankruptcy protection.

The board will now meet to discuss its “next steps” after a large number of investors refused to exchange their debt for company shares.

Meanwhile, the German government is set to begin a series of meetings later to consider bids for GM’s Europe arm.

Four bidders are currently in the running for Opel and UK’s Vauxhall.

Owner General Motors will have the final say, but the German government’s backing is crucial, as GM would struggle to do a deal without it.

But a spokesperson for UK Business Secretary Lord Mandelson said GM wanted to keep talking with all bidders. All had committed to maintain Vauxhall production in the UK, he added.

Bidding war

German Chancellor Angela Merkel will be meeting GM representatives and US government officials at 2000 BST on Wednesday night.

Her government is being asked to put up hefty loan guarantees for the winning bidder for GM Europe, so its backing could sway US parent GM’s ultimate decision on who to sell to.

This is because Opel has its headquarters in Germany, and 25,000 of the firm’s 50,000 workers are employed in the country.

The four bidders for GM Europe are Italy’s Fiat, Canada’s Magna, Belgium’s RHJ and China’s Beijing Automotive Industry Corporation (BAIC).

With an election looming, Berlin does not want to see too many job losses arising from the takeover.

Magna says it will lay off 2,500 workers in Germany, while Fiat says it will cut 10,000 jobs across Europe, including 2,000 in Germany.

BAIC, however, says it will not cut any jobs for at least two years.

But the takeover will also affect 5,000 Vauxhall workers at plants at Ellesmere Port and Luton in the UK, and there are fears that the German government’s influence could prejudice UK jobs.

Derek Simpson, general secretary of the Unite union in the UK, fears the Germans will support a bid which offers no protection to British workers.

The UK government has said it might consider making a financial contribution to help secure the future of Vauxhall.