The injured includes many female students and six among them were said to be in critical condition, said our correspondent.

According to Bomb Disposal Squad, about 40kg explosives were used in the remote-controlled bomb, planted inside a car which was parked nearby.

Four police officials were also injured as a police mobile passed by.

The attack took place on the outskirts of Quetta, the capital of the oil and gas rich Baluchistan province that borders Afghanistan and Iran.

“An improvised-explosive device planted underneath a car parked on the roadside exploded near the bus of the local IT university, killing four students at and wounding 65 others, mostly students,” said local police official, Muhammad Anwar.

“It was not immediately clear if the bus was the target but we are investigating,” he added.

Another local police official, Akbar Shawani, confirmed the casualties. He said that the bus was taking the students to their university.

There was no claim of responsibility for the attack. AFP