KARACHI, Pakistan — A Pakistani railroad official says a passenger train has collided with a freight train in the southern city of Hyderabad, killing three people and injuring several others.

Mohammad Rizwaz, Hyderabad station superintendent, says the exact cause of Thursday's collision was unclear and authorities were still investigating.

The passenger train was traveling to the eastern city of Lahore from the port city of Karachi when it collided with a freight train.

According to Railways Minister Sheikh Rashid Ahmed, authorities transported the injured to a hospital.

Hyderabad is in southern Sindh province.

Train accidents are common in Pakistan, where decades-old tracks are often poorly maintained.