At least four people, all civilians, were killed and three others injured as a car bomb rocked Afghan capital city Kabul on Friday, Interior Ministry spokesman Nasratullah Rahimi said.

According to Rahimi, the car bomb, obviously targeted a convoy of foreign forces in Qala-e-Wazir area, a neighborhood in Police District 9 at 8:40 a.m. local time, on Kabul-Jalalabad road in the eastern edge of Kabul city.

However, he added that investigation is under way and the figure of casualties may go up.

This is the second deadly blast in Kabul over the past two days.

In the previous blast that targeted a military college on Thursday, seven people lost their lives and six others sustained injuries.

Although no group has claimed responsibility, the officials do not rule out the involvement of Taliban outfit in the bombings.