In April 2004, in Compound 4, a riot broke out in which detainees threw rocks and fashioned weapons out of tent poles. Detainees held a military soldier hostage until the riot was dispelled by the use of lethal force. Four detainees were killed and six were injured. As is standard procedure in all cases of prison riots and the use of lethal force, the matter was investigated by the U.S. Army's Criminal Investigations Division. The investigation concluded that a detainee leader had incited the riot by making an accusation that camp soldiers were stepping on Korans during a search for contraband. No soldiers were found guilty of any wrongdoing during the incident.