Washington (CNN) -- A U.S. federal appeals court Friday overturned a court decision to release a Guantanamo detainee accused of helping al Qaeda.
Mohammedou Ould Salahi was set to be released after a lower court ruled the government could not prove his association with the terrorist network, but the decision was reversed in light of recent trial cases that raised questions over how an individual is determined to be part of al Qaeda.
The earlier ruling identified Salahi as an al Qaeda "sympathizer," but the lack of recent cases "left unresolved key factual questions necessary for us to determine as a matter of law whether Salahi was 'part of' [al Qaeda] when captured," according to the appeals court order.
The ruling sides with the Justice Department by vacating the judge's order to release the Guantanamo detainee.
The 9/11 commission, which investigated the 2001 attacks on the United States, identified Salahi as a person who encouraged two of the eventual hijackers and a third man to seek al Qaeda training in Afghanistan in October 1999.
Salahi was never released from custody during the appeals process.