Bannu police chief Mohammed Alam Shinwari said at least seven people died Friday after a suicide car bomber rammed into a police car in the Pakistani city before the bomber's vehicle exploded, the PakTribune reported.

Four police officers were among those killed in the suicide blast, Shinwari said.

The Associated Press of Pakistan said an estimated eight people were injured in the explosion and some of those hurt were said to be in critical condition at an area hospital.

Up to four people died Thursday in a similar suicide blast in the Afghan capital of Kabul, city police head Ali Shah Paktiawal told PakTribune.

Witnesses to the bombing said a suicide car bomber targeted foreign forces traveling through the city.

Four Afghan nationals were killed in the attack, while three others were wounded.

The PakTribune said no group has claimed responsibility for the attack that occurred near the city's Massoud Square.