Pakistani officials say at least 35 passengers have been killed and dozens more injured in two separate bus accidents that occurred hours apart. The first happened early Sunday when a bus carrying Shiite Muslim pilgrims returning from Iraq through Iran fell from a highway into a ravine in southwest Pakistan, killing at least 12 people and injuring 32 others. Hours later, 23 people were killed when a bus fell into a ravine in Kahuta district in the eastern Punjab province. Bus accidents are common in Pakistan, mostly because of the negligence of the drivers who often violate traffic rules.