An Afghan policeman has killed nine colleagues in an attack in the eastern province of Paktika, the latest in a string of rogue shootings that have also targeted foreign forces.
The assailant is believed to have laced the victims' dinner with crushed sleeping pills, then shot them dead as they slept.
Provincial police chief Dawlat Khan Zadran says he then picked up the officers' weapons and drove off in a vehicle.
Two of his brothers have since been arrested.
The Taliban says the attacker came to them soon after the shootings, bringing the vehicle and the weapons taken from the dead policemen.
"He has joined our mujahideen," a spokesperson said in a text message to journalists.
A series of attacks on NATO personnel by Afghan army and police personnel has stoked fears the security forces have turned against their western allies, or have been infiltrated byTaliban insurgents.
Tension between Afghanistan and its foreign backers has risen after incidents including the burning of copies of the Koran at a NATO base, and a massacre of 17 villagers for which a United States soldier has been charged.