The official said five members of the militia were killed. (Representational Image: ANI)

An Iraqi official says an airstrike has hit two cars carrying Iran-backed militia north of Baghdad, one day after US attack on top Iranian general Gen Qassem Soleimani.

The official said five members of the militia were killed.

The official said the identity of those killed was not immediately known. He spoke on condition of anonymity because he was not authorized to talk to reporters.