The logo of the U.S. Central Intelligence Agency is shown in the lobby of the CIA headquarters in Langley. Reuters

The government is renewing investigations into two cases that could indicate serious lapses in the Central Intelligence Agency's (CIA) methods of detaining and questioning terror suspects, the Associated Press reported.

The CIA's inspector general has begun reexaming how the agency confused a vacationing German citizen for a terrorist and wrongfully imprisoned him for months, while the Justice Department is looking into allegations that a suspect died as a result of harsh interrogation practices at Abu Ghraib prison in Iraq.

The ongoing inquiries, which are being conducted secretly, underscore debate over the effectiveness of the Bush administration's counterterror policies.

The Obama administration has continued some of those policies, including the practice known as secret rendition in which suspects are transported to third party countries for questioning. The German citizen, Khaled el-Masri, was detained using that mechanism. While the Justice Department has already examined his case, it exonerated the counterrorism analyst who signed off on the operation.

In the second case, a detainee named Manadel al-Jamadi died after his arms were chained to a barred window to prevent him from moving them without experiencing pain. A military autopsy finding the death to be a murder was contradicted by a subsequent CIA investigation finding that Mark Swanner, who questioned al-Jamadi, had not abused him. A CIA who ran the detainee unit at Abu Ghraib is the subject of the current investigation, which is examining whether he missed a chance to prevent al-Jamadi's death.