At least 34 people were killed, mainly women and children, and 17 others injured in western Afghanistan on Wednesday when the bus they were travelling in hit a roadside bomb, officials said.

The attack occurred around 6:00 a.m. local time (0130 GMT).

"A passenger bus travelling on the Kandahar-Herat highway hit a Taliban roadside bomb," said Muhibullah Muhib, the spokesman for Farah province.

There has been no immediate claim of responsibility from the Taliban or any other group.