The US military cannot account for 190,000 AK-47 assault rifles and pistols given to the Iraqi security forces, an official US report says.
The Government Accountability Office (GAO) says the Pentagon cannot track about 30% of the weapons distributed in Iraq over the past three years.
GAO, the investigative arm of the US Congress, said at least $2.8bn of this money was used to buy and deliver weapons and other equipment.
Correspondents say it is now feared many of the weapons are being used against US forces on the ground in Iraq.
The GAO said weapons distribution was haphazard and rushed and failed to follow established procedures, particularly from 2004 to 2005.
The US military commander in charge of training in Iraq has asked for help in speeding up the transfer of equipment.
Iraq's ambassador to the US said the delays were hindering the fighting capacity of its armed forces.
clipped from: news.bbc.co.uk