At least 35 Taliban and Pakistani militants were killed and 25 wounded in a security force operation in Zabul in search of the 31 bus passengers, local officials said Thursday.

Zabul provincial acting-governor Ashraf Nasiri said that the operation was conducted in the Khak Afghan district to rescue the passengers who were kidnapped more than two months ago.

The operation started two days ago in Qalat center of Farah province and Shah Joe district and still on going.

18 Pakistani militants and six Taliban local commanders are among the death. Nasisri added.

So far however the passengers have still not been found.

This comes three days after Zabul local officials said 26 insurgents had been killed in Shah Joy district.

There is no report on civilian casualties.

Taliban has yet to comment on the operation.