KHOST: A suicide bomber struck at a lunch gathering of Afghan police and local civilians in southeast Afghanistan on Saturday killing at least 13 people, three of them policemen, officials said.

The attacker, wearing a suicide vest, walked into a police checkpost in the troubled district of Alisher in Khost province and detonated himself, a statement issued by the provincial governor's office said.

“Unfortunately as a result of this cruel and inhumane attack ten civilians including two children and three policemen were martyred while five policemen and and one child were injured,” the statement said.

Local district governor Amir Badsha Dawran earlier told AFP the assailant shot dead a security guard before making his way into the checkpost.

According to Dawran, the locals in the area were having regular “friendly”meetings with security forces to discuss various issues including security in the area.

Taliban insurgents claimed the attack, saying that all the casualties were Afghan security forces.

Khost is a volatile province which borders the tribal area of Pakistan, known as a Taliban stronghold and a base for the Haqqani network.

The Taliban and other militants frequently target Afghan security forces as part of their campaign to bring down the western-backed Kabul government.

Civilians however bear the brunt of the decade-long war.

According to the United Nations, civilian deaths from the Afghan conflict reached a record-high last year, when 3,021 died in the violence, with the Taliban blamed for the bulk of the casualties.

There are currently around 130,000 international troops in Afghanistan, two-thirds of them from the United States.

But the Afghan police and army are to take on more responsibility for security as foreign combat troops withdraw in a process due to be completed by the end of 2014.