According to local government officials, the incident took place earlier this morning on Farah-Herat highway, Khaama Press reported.
The officials further added that the militants had briefly blocked the highway before abducting the passengers.
A member of the provincial council Dadullah Qaneh confirmed the incident and said the issue of the road blockage by the militants has been resolved but there are not reports regarding the fate of the hostages.
The anti-government armed militants have not commented regarding the incident so far.
Farah is among the relatively volatile provinces in western Afghanistan where anti-government armed militants are actively operating in a number of its districts.
The anti-government armed militants have recently stepped up kidnapping civilians on main highways of the country, mainly for ransom and target killings.
Militants also kidnapped five passengers on Kabul-Jalalabad highway in the vicinity of Laghman province earlier this month with local officials saying the civilians were dropped from their vehicle in Khairokhil area of Qarghai District on gunpoint and taken to an unknown location.