RAPE is being used as an instrument of torture by Sri Lankan security forces to extract confessions from suspected Tamil separatist supporters, Human Rights Watch has alleged.

As a United Nations Human Rights Council meeting that will examine Sri Lanka's civil rights record begins in Geneva, a report released by Human Rights Watch, We Will Teach You a Lesson, details 75 statements from Tamil victims who say they were raped and tortured by soldiers, police and other pro-government paramilitary groups.

Thirty-one of the victims allege they were raped after the cessation of Sri Lanka's long-running civil war in May 2009.

The last case in the report was in October last year but the rights group said the practice is continuing and that the 75 cases outlined represent a tiny fraction of the total sexual assaults.

''The Sri Lankan security forces have committed untold numbers of rapes of Tamil men and women in custody,'' said Brad Adams, the executive director of Human Rights Watch's Asia division.

''These are not just wartime atrocities but continue to the present, putting every Tamil man and woman arrested for suspected LTTE [Liberation Tigers of Tamil Eelam] involvement at serious risk.''

Sri Lanka's military spokesman Ruwan Wanigasooriya rejected all of the allegations, saying they lacked credibility. He said the report consisted of ''fabricated allegations'' and ''good creative writing''.

Sri Lanka's High Commissioner to India said there was no evidence to substantiate the claims. Prasad Kariyawasam said the testimonies of 41 women, 31 men and three boys were likely made by ''economic refugees'' who ''need a good story'' to claim asylum.

The 75 case studies presented by Human Rights Watch bear strong similarities. All allegations, the rights body said, have been corroborated by medical and legal reports.

One man, 21-year-old ''DK'', alleges he was snatched from the street by two men in a white van in August last year. He was held in a room and interrogated.

''One of the men in civilian clothes accused me of being an LTTE member,'' he said. ''I denied all their allegations. Two other men came into the room. They started beating me with plastic pipes filled with sand, batons and forced a petrol-infused bag on my head and tried to asphyxiate me. They burned me all over with cigarettes during the questioning.

''At night, when I was in a small room, a man in civilian clothes came and started touching me indecently. He told me to have oral sex with him. When I refused, he beat me and raped me. This happened every night for four or five nights. I signed the confession when I could not bear this torture any more.''

with agencies