The "highest levels" of Sri Lanka's government were complicit in raping, torturing and abducting ethnic Tamils following the nation's ethnic civil war, a report by rights groups warned today.

Authorities carried out horrific sexual abuse on Tamils, including forced oral sex and anal rape as well as water torture, the report by the UK Bar Human Rights Committee and International Truth & Justice Project found.

It comes ahead of next week's UN Human Rights Council debate on a US-led resolution calling for an international probe into alleged war crimes in Sri Lanka. Yasmin Sooka, a top South African human rights lawyer and UN adviser, compiled the report from interviews with 40 Tamils who said they were held in custody by Sri Lankan authorities.

"Sri Lanka's military is still waging a campaign of persecution using abduction, arbitrary detention, torture, rape and sexual violence" after the crushing of separatist Tamil rebels in 2009, Sooka said.

Read more on Business Standard