KABUL, Afghanistan (AP) -- Motorcycle-riding gunmen assassinated a police chief in front of his house after he led an anti-Taliban campaign in western Afghanistan, an official said Saturday.

Police Chief Abdul Ghani was leaving his driveway in his car outside his home in Farah province when the two raced up and opened fire.

Provincial spokesman Abdul Rahman Zhawandai said that Ghani was rushed to hospital after the attack Friday night but died of his wounds.

Ghani had recently launched a crackdown against insurgents in his district of Khaki Safad that resulted in the killing and capture of several Taliban leaders, Zhawandai said.

"Because he was an active commander in this district, he was a target of the Taliban," he said.

In the same province Saturday morning, four Afghan army soldiers died in Bakwa district when their vehicle hit a roadside bomb, the Defense Ministry said in a statement.

Afghan security forces and government officials are targeted by the Taliban to weaken the government of President Hamid Karzai ahead of the withdrawal of most international troops by the end of 2014.