Provincial governor spokesman Attaullah Khogyani told Ariana News that the explosion took place in the Abdul Haq Mena area of Jalalabad city on Sunday noon.
He said the explosion hit a police car which left two policemen wounded.
According to another source, the target of the explosion has yet to be identified as the police car was struck by the bomb shortly after a convey of a public upraising commander Haji Hayat Khan crossed the road.
No one immediately claimed responsibility for the attack.
This comes as yesterday at least two U.S. service members were also wounded when their vehicle struck a roadside mine while they were conducting a patrol near the airport on the outskirts of Jalalabad city.
Nangarhar is among the volatile provinces in east of Afghanistan where the Taliban and the extremist Islamic State (IS) militants are actively operating in a number of its districts and usually carry out attacks against Afghan forces.