Twenty people have been killed and 50 others injured after a team of suicide bombers shot their way into the compound of a road building company in eastern Afghanistan and detonated a lorry loaded with explosives, the Afghan government said.
The attack occurred in the Barmal district of Paktika province late on Sunday, the Interior Ministry said.
It said three attackers went up to the gate of the Zahir construction company, shot the guard and then drove a large truck full of explosives into the compound, where they detonated it.
The area is on the border with Pakistan's lawless tribal regions, which serve as safe havens for insurgents who infiltrate into Afghanistan across the mountainous frontier.
The region has seen an escalation in violence over the past few months.
Taliban spokesman Zabiullah Mujahid claimed responsibility for the attack, saying it was the work of a suicide bomber. He said in an emailed statement that it was targeting a joint Afghan-Nato operating base.
Mokhlis Afghan, spokesman for provincial Governor Mohibullah Samim, said all the dead and injured were labourers and there were no Afghan or foreign forces at the site. He added that the explosion was so powerful that little remained of the truck.
The Afghan spokesman said "all the casualties are innocent civilian people. They are all poor people who were working as labourers in a construction company. No Afghan security or international forces were involved. The Afghan army and Nato helped carry the injured to hospitals."