KABUL: At least 17 people were killed in a suicide attack and other incidents of violence on Saturday.

A disguised bomber gunned down a security guard and then detonated explosives at the government offices, with two state prosecutors also among his victims, Nimroz provincial governor Ghulam Dastgir Azad said.

The blast brought down the single-storey building in the town of Zaranj on the southwestern border with Iran, the governor said.

"We have recovered so far six bodies," he said. The dead were provincial attorney Anwar Shah Khan, his 20-year-old son, his deputy and three civilians, Azad said.

"The whole building has collapsed. There might be more casualties," he added.

A spokesman for the rebel Taliban movement said the bomber was a member of the militia, which has dramatically stepped up attacks this year.

There has been a wave of suicide blasts in Afghanistan in the past three years, most of them claimed by Taliban extremists who are waging an insurgency against the US-backed government in Kabul.

Elsewhere in Nimroz, about 150 Taliban militants attacked a police post early Saturday, killing two policemen but losing eight of their own fighters, Azad said.

Also Saturday, insurgents attacked another police post, in Laghman province, near the Afghan capital Kabul, leaving one policeman and two rebels dead, provincial police chief Abdul Karim Omeryar said.