Local security officials confirming the report said the incident took place late Saturday evening in the central city of Sar-e-Pul province.
Provincial security chief, Sakhidad Haidari said, at least three policemen were killed and four others were injured after their vehicle struck witht the roadside bomb.
In the meantime, Gen. Zahir Azimi, spokemsan for the defense ministry of Afghanistan said at least two Afghan national army soldiers were killed following two separate explosions in southern Afghanistan.
Gen. Zahir Azimi said teh two soldiers were killed following roadside bomb explosions in Kandahar and Uruzgan provinces.
No group including the Taliban militants has so far claimed responsibility behind the two incidents.
Taliban fighters frequently use improvised explosive device (IED) as the weapon of their choice to target Afghan and coalition security forces.