At least five people were killed and 15 injured when a bus overturned in Pakistan's Punjab province Thursday, officials said.According to police and rescue officials, the passenger bus went out of control and overturned on a sharp turn near Fatyana Chowk area of Kamalia district, about 240 km southwest of Lahore, Dawn online reported.Five people died on the spot while 15 passengers sustained injuries, officials said.Some of the injured passengers were said to be in critical condition.The injured were shifted to the Kamalia district headquarter hospital.Police claimed the accident occurred because of over-speeding and reckless driving.