At least 34 people, including women and children, were killed in a roadside bomb blast in Herat-Kandahar Highway early on Wednesday morning, local officials said.
The incident happened in Shawiz area when a bus carrying dozens of passengers was travelling to Farah province from the western province of Herat, an official of Herat hospital, Mohammad Ibrahim Mohammadi, said.
At least 17 others, including women and children, were wounded in incident, he said.
Security officials have not commented on the incident.