At least 34 civilian passengers, mainly women, and children have been killed in Afghanistan when the bus they were traveling in ran over a roadside bomb.

"A passenger bus traveling on the Kandahar-Herat highway hit a roadside bomb," said Muhibullah Muhib, a spokesman for western Farah province, of the incident on Wednesday morning. All were civilians, mostly women and children, he said.

Farooq Barakzai, a spokesman for Farah's governor, confirmed the toll but warned it might rise.

No one has yet claimed the attack. (ILKHA)