DHAKA: The CIA repeatedly misled the US government over the severity and effectiveness of its interrogation methods.

The Washington Post reports, according to the BBC.

A long-awaited US Senate report said that the CIA used secret ‘black sites’ to interrogate prisoners using techniques not previously acknowledged.

These included dunking suspects in icy water and smashing a prisoner’s head against a wall.

The findings stem from the time of former president George W Bush.

Officials familiar with the secret document said that the CIA’s interrogation program yielded little useful intelligence.

They also said that this intelligence had then been exaggerated so that the interrogation program looked more effective than it actually was.

The report is the result of a wide-ranging investigation by the Senate intelligence committee into CIA activities which began in 2009.

The committee will meet on Thursday to decide on whether to send a summarised version to president Barack Obama for eventual public release.

BDST: 1758 HRS, APR 01, 2014