The incident took place when a roadside bomb hit their vehicle in Dand district of the province.
Provincial governor spokesman Aziz Ahmad Azizi said, as a result, six civilians including two women and two children lost their lives.
All the victims were members of a family.
He blamed the Taliban insurgent group for the explosion.
Taliban has not made a comment about the report yet.
On June 9, the UN mission in Afghanistan said it “remains troubled that civilians are being killed in high numbers” in the Afghan conflict, and urged all warring parties to protect civilians from harm.