A United Nations committee that monitors acts of torture in member countries has grilled a Sri Lankan intelligence chief over the alleged abuse of detainees during the country's civil war.

A U.N. report last year documented evidence of "premeditated and systematic" torture by Chief of National Intelligence Sisira Mendis' subordinates when he was a top police official during the recent war.

The evidence included equipment allegedly used for beatings and waterboarding.

Mendis' presence at the Committee Against Torture's hearing on Sri Lanka surprised both panel members and non-governmental groups that have raised concerns about his war-time activities.

Mendis did not respond to the committee's questions Wednesday. Sri Lanka Attorney General Jayantha Jayasuriya stepped in to deflect the inquiry, saying the country's delegation would respond in writing within 48 hours.