Reliance on private security contractors in Afghanistan has ended up lining the pockets of Afghan warlords, a US Senate inquiry has found.
The inquiry, by the Senate Armed Service Committee, said funds had sometimes been funneled to warlords who were linked to the Taliban, murder and kidnapping.
It found private security forces were often poorly trained and supervised by their companies and inadequately overseen by Defense Department contract managers.
"All too often our reliance on private security contractors in Afghanistan has empowered warlords, powerbrokers operating outside Afghan government control," Democratic Senator Carl Levin said in releasing the report.
"There is significant evidence that some security contractors even worked against our coalition forces, creating the very threat they are hired to combat," he added. "These contractors threaten the security of our troops and risk the success of our mission."
Richard Fontaine, a senior fellow at the Center for a New American Security, said the committee report "fills out a picture many have already suspected - that taxpayer dollars in Afghanistan at times end up in the hands of those we are fighting."
"It is another wake-up call that the US needs to take aggressive steps to get a better handle on contractors and subcontractors in Afghanistan," said Mr Fontaine, who authored a June report on contracting.
"Getting a better handle on who is doing what, with what money and where that money is going, should be priority number one," he said.
Some 26,000 private security personnel - a large proportion of them Afghan nationals - were operating in Afghanistan under US Defense Department contracts as of May 2010, the report said, citing figures from the US Central Command's Armed Contractor Oversight Directorate.
Afghan president Hamid Karzai issued a decree in August giving foreign security contractors four months to disband. The Interior Ministry said on Sunday it had moved to shut down eight firms, seizing 400 weapons.
Private security firms in Afghanistan provide guards for everything from embassies and aid agencies to supply convoys and US military bases.
While providing vital services in the war-torn country, they have become a point of friction because of the involvement of some in high-profile shooting and other incidents.
Agencies