A provincial police chief says militants have released 148 Afghan labourers who were held hostage for almost a week in western Afghanistan.

Militants last Sunday stopped three buses carrying labourers and abducted everyone on board.

The labourers were working on a military base for the Afghan army in the city of Farah.

Khalilullah Rahmani says 118 of the workers were released on Friday and that around 30 were released on Saturday. Rahmani is the police chief of Farah province.

Rahmani says Afghan elders helped secure their release and that no ransoms were paid.

No one immediately claimed responsibility and the Taliban have denied involvement.

Rahmani says he does not know who kidnapped the workers.