Some remnant WMD were scattered at various locations throughout Iraq, but most were old and unusable. During the US occupation of Iraq, weapons were occasionally discovered and destroyed. On occasion, these would test positive for chemical weapons. Most of the chemical warheads were left over from the Iraq-Iran war, and none newer than 1991. The majority of chemical weapons were found near the Muthanna State Establishment not far from Bahgdad. US and Iraqi personnel sustained injuries on six documented cases during 2004-2011. However, most of the details remain classified.