— President Hamid Karzai’s government is accusing the U.S. and British military of operating secret detention facilities in Afghanistan, a development that could further strain relations between Afghanistan’s leader and the West.

After receiving reports about Afghan detainees at coalition bases, Karzai established a fact-finding commission to study the matter. On Tuesday, it announced that it had found six detention centers that run afoul of an Afghan law requiring all prisoners from the country be held in Afghan-run jails.

Abdul Shokur Dadras, a member of the commission, said two of the jails were overseen by British soldiers at Camp Bastion in Helmand province, while a third jail at that base was under American military control. At Kandahar Airfield, also in the southern part of the country, three more foreign-run prisons were discovered — one controlled by American soldiers, one by the British and one managed by a joint coalition force, Dadras said.

“The prisons are in clear contradiction of the president’s order, which says that foreigners cannot run prisons, hold Afghans as detainees or investigate them,” Dadras said in an interview, adding that the facilities must be closed immediately.

In separate statements, Pentagon and coalition officials appeared surprised that Afghan leaders had chosen to make an issue out of the matter.

From Kabul, the U.S.-led military coalition said that “every facility that is used by coalition forces for detention is well known” by the Afghan government and is routinely monitored by the Red Cross.

“We are waiting to receive the commission’s official report to better understand the basis of the allegations and findings,” the statement said.

In Washington, a U.S. official familiar with the matter said Dadras appears to be referring to detention facilities that NATO troops use to hold detainees for up to 96 hours after they are picked up on the battlefield by foreign troops.

“These are sites the Afghans know about,” said the official, who spoke on the condition of anonymity because he was not authorized to be quoted by name.

Dadras said the commission discovered one prisoner who had been detained for 31 months.

“It’s a clear violation of Afghan laws and Afghan sovereignty,” said Karzai spokesman Aimal Faizi. “We have been in direct contact on this issue with American and British officials.”

The committee’s findings were first reported Saturday by the New York Times.

On Tuesday, there was still some confusion about how many Afghan prisoners were found by the fact-finding team. Dadras said detainees were found at all sites except the joint-coalition-operated facility at Kandahar Airfield.

But the Associated Press, quoting commission leader Gen. Ghalum Farooq Barakzai, reported six Afghan detainees were discovered at the British-run facility at Kandahar Airfield while 17 were at the British jail at Camp Bastion.

Barakzai told the wire service that the panel found no prisoners in any American-run jails.

The allegations come at a sensitive time in the relationship been Washington and Karzai, who is in the final months of his presidency.

For months, Karzai has refused to sign a security agreement that would allow a residual force of American troops to remain in Afghanistan after the end of this year, when most NATO troops are scheduled to withdraw.

He has also repeatedly lashed out at the U.S. military over allegations of civilian casualties.

In February, Karzai ordered the release of 65 Taliban prisoners from Bagram prison outside Kabul, ignoring repeated pleas from U.S. military commanders and diplomats to hold off since the prisoners were likely to return to the battlefield.

Tim Craig in Kabul and Ernesto Londoño in Washington contributed to this report.