The Sri Lankan Government has blocked access to aid workers trying to help the nearly 300,000 civilians displaced by the army’s victory over the Tamil Tigers, raising the prospect of a humanitarian catastrophe.

In the capital, Colombo, President Rajapakse announced the “complete defeat” of the rebels yesterday as state television showed pictures of what was said to be the corpse of Velupillai Prabhakaran, the Tigers’ leader. Mr Rajapakse vowed in an address to the nation to press ahead with a “homegrown political solution” to end ethnic divisions between the majority Sinhalese population and minority Tamils.

As he spoke, an estimated 80,000 people — mostly Tamil, many of them sick, malnourished or suffering from battlefield wounds — were making their way on foot from the war zone In the north to government-run camps that are already swamped. The UN is not being allowed any access to them, The Times has learnt.

Accounts of conditions inside the camps — gained from testimony recorded covertly by aid workers — and the journey to them are horrifying.

Preema, a Tamil woman, arrived at the 400-hectare (990-acre) Menic farm camp on Sunday. She had left Mullaivaikal, the centre of the fighting, where the Tigers had made their final stand before being defeated, days before, after being shelled heavily.

She set out with her husband, mother and two children, to wade through the Nandikadal lagoon — a waterway strewn with mines — in a desperate attempt to reach safety.

There were deep craters where the lagoon had been bombed and people often drowned, she said. A man offered to carry her ten-year-old daughter. Preema never saw them again. Her husband was taken away later by government troops at a checkpoint in Oomanthai, where refugees are being forced to strip before being allowed to pass, after admitting that he had worked for the Tigers. Her mother died in the lagoon.

“Everything is lost,” said Preema, holding her son, 7. “Please help me find my daughter. Not knowing anything is making me crazy.”

Inside one camp, Nandani, 76, described being forced to stand for up to five hours a day queueing for food.

Kala, a middle-aged woman, spoke about the constant indignities of her new life. “I do not have underwear. I am unable to use the Kotex that the Red Cross handed out,” she said, holding a packet of sanitary towels she had been given before the organisation’s access to the camp was restricted.

Kothai, another woman, said: “There is a bad distribution system within the camp. Every time it is the same people that get \. Men crowd around and push the women and children aside.”

Government officials did not answer requests for comment. Access for aid agencies to another 200,000 refugees already in the internment camps — which the Government call “welfare villages” — has been severely restricted since Sunday, preventing the administration of basic care.

Ban Ki Moon, the UN Secretary-General, is due to travel in Sri Lanka on Friday to offer help to rebuild the ravaged northeast of the country and urge the Government to reach out to the Tamil population.

“These people have endured one of the cruellest military sieges of modern times — daily shelling over several months,” an international aid worker said. “They need urgent help.” There are fears that the camp populations — especially children — will be hit by contagious diseases. Chickenpox, hepatitis A and dysentery outbreaks have been reported. Medical facilities are said to be woefully inadequate.

There are also concerns that the suffering will radicalise previously moderate Tamils, especially amongst the community’s international diaspora, which had been a key source of funding for the Tigers.

Most Sri Lankans are delighted by the defeat of the Tigers, a terrorist force that fought for 26 years for an independent Tamil homeland, propagating a war that left at least 70,000 dead. Many Tamils were against the rebels after they recruited child soldiers and terrorised their own people.

Tamils in the camps describe being fired on by both sides in the conflict.

Vavathan, 59, said that Tiger troops had forcibly recruited children as young as 15 in the conflict zone, even in the final stages when it was clear that they had lost the conflict. “The war was over, why were they still taking the children?” she asked.

There were doubts over the sincerity of Mr Rajapakse’s pledge to build bridges between the Sinhalese and Tamil minority. He has seldom brooked dissent, his opponents say.

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