The men, who looked well-fed but nervous, denied they were withdrawing their statements under pressure, even as they expressed hopes they might now be released.

A rights group said there were "significant grounds to question whether these statements were voluntary."

Their new testimony - with drastically reduced death tolls and other casualty figures - contradicted reports from independent aid workers with the United Nations and the Red Cross who also witnessed some of the violence.

The government barred journalists from the war zone and threw out most aid workers, leaving the doctors as one of the few sources of information about the toll the fighting was taking on hundreds of thousands of civilians trapped by the final battles of the 25-year civil war.

U.N. figures show that 7,000 civilians were killed between January and May.

The doctors estimated yesterday that 650 to 750 civilians were killed during that period.

Human-rights groups accused the government of shelling populated areas and accused the rebels of holding civilians as human shields. Satellite photos showed densely populated civilian areas had been shelled. Both sides denied the accusations.

When asked about the doctors' comments, U.N. spokesman Gordon Weiss said: "We stand by our statements."

At the time, the doctors gave harrowing accounts of the damage and described how the vast number of wounded civilians overwhelmed their makeshift hospitals as they ran low on food, medicine, supplies, and staff.

The interviews infuriated government officials, who denied the men existed, then insisted the doctors were being misquoted, and finally said they were under pressure from the rebels to lie.

The doctors fled the area during the final battles in mid-May and were immediately arrested and accused of spreading rebel propaganda.

Yesterday, five doctors were brought before foreign and local media and they said the Liberation Tigers of Tamil Eelam rebels had forced them to exaggerate the damage caused by the shelling and gave them lists of casualty figures to give to media.

The rebels took medicine and food shipments sent by the government and demanded the doctors tell the media there were shortages, the men said.

"The information that I have given is false. . . . The figures were exaggerated due to pressure from the LTTE," said one doctor, V. Shanmugarajah.

However, Sam Zarifi, Asia-pacific director for Amnesty International, said the statements from the doctors were "expected and predicted."

"Given the track record of the Sri Lankan government, there are very significant grounds to question whether these statements were voluntary, and they raise serious concerns whether the doctors were subjected to ill-treatment during weeks of detention," he said.