Mohammad Juma Adil, a commander of the border protection police forces in western Afghanistan said, the incident took place late Saturday in Shindand district.
Mr. Adil further added that the incident took place after the vehicle of the border protection police forces struck with the improvised explosive device (IED), leaving three officers injured.
However, a security official in Herat province has said that the blast left one police officer dead and three others injured.
No group including the Taliban militants has so far claimed responsibility behind the incident.
Local officials blame the Taliban group for the incident, as Taliban fighters frequently use improvised explosive device (IED) to target Afghan and coalition security forces.