Islamabad, Dec 29 (IANS) At least five people were killed and 45 injured Saturday in an explosion in a bus stand in Pakistan’s port city Karachi, a media report said.

The blast took place around 3 p.m. when a passenger bus was passing by in Cant Station area, Xinhua reported. But it was not clear what caused the explosion.
Hospital officials said five injured people were in critical condition.
The bus was on its way from Karachi to Sargodha.
Chaudhry Aslam, superintendent of the Crime Investigation Department, said the blast may have been caused by a cylinder explosion.
Some witnesses, however, said explosive materials were probably fixed on a motorbike parked near the bus stand.
Another report said the explosive material may have been hidden inside the luggage of one of the passengers.