The attack in Pul-i-Alam, some 80 kilometers (50 miles) east of Kabul and the capital of Logar province, started when the first bomber detonated his explosives at the gate of the police headquarters, said Din Mohammad Darwesh, a spokesman for the provincial governor.
A second attacker blew himself up at a security checkpoint inside the compound, then other bombers ran into a dining hall where policemen had gathered to eat lunch, killing several more officers.
Gen. Abdul Hakim Esaqzai, the police chief of Logar province, said the bombing killed at least 20 people, including two civilians. He said the attack also wounded eight people.
The bombers wore police uniforms, allowing them to get inside the compound, said Muhibullha Ghayrat, a member of Logar's provincial council.
Taliban spokesman Zabihullah Mujahid claimed responsibility for the attack in an email sent to The Associated Press.
The Taliban have stepped up their attacks on Afghan soldiers and security forces in recent months. U.S. and NATO forces concluded their combat mission at the end of last year and Afghan troops since have taken control of the country's security. That's caused Afghan casualties to spike.
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