A secret video showing US air crew falsely claiming to have encountered a firefight in Baghdad and then laughing at the dead after launching an air strike that killed a dozen people, including two Iraqis working for Reuters news agency, was revealed by Wikileaks Monday. The footage of the July 2007 attack was made public in a move that will further anger the Pentagon, which has drawn up a report identifying the whistleblower website as a threat to national security. The US defence department was embarrassed when that confidential report appeared on the Wikileaks site last month alongside a slew of military documents. The newly released video of the Baghdad attacks was recorded on one of two Apache helicopters hunting for insurgents on 12 July 2007. Among the dead were a 22-year-old Reuters photographer, Namir Noor-Eldeen, and his driver, Saeed Chmagh, 40. The Pentagon blocked an attempt by Reuters to obtain the video through a freedom of information request. Wikileaks director Julian Assange said his organisation had to break through encryption by the military to view it. Wikileaks says it will shortly release a second secret US military video showing the deaths of civilians in an attack in Afghanistan. The Pentagon has been seeking ways to prevent classified material appearing on Wikileaks, including through “criminal sanctions”. Wikileaks has made public classified US army reports on weapons, military units and battle strategy in Iraq and Afghanistan.