Four suicide attackers stormed a provincial police headquarters in eastern Afghanistan on 17 February killing 22 police officers, an official said.
Taliban insurgents immediately claimed responsibility for the attack in Logar province outside the capital, Kabul. It is the latest to target Afghan security forces following the withdrawal of most foreign combat troops at the end of last year.
The attackers rushed the gates of the police compound in the early afternoon, with one detonating his explosives-filled vest at the main gate and killing one policeman, Logar government spokesman Din Mohammad Darwish said.
The attack triggered a 25-minute battle with police.
Twenty-one police were killed and seven wounded when another of the bombers detonated his vest, said Abdul Wali Toofan, Logar's deputy police chief. The other two attackers were killed with no further casualties.
Zabihullah Mujahid, a spokesman for the Taliban, claimed responsibility on his official Twitter feed.
Earlier on Tuesday, a bomb attached to a vehicle wounded one person in Kabul, police said, breaking a recent lull in attacks in the Afghan capital.