Pakistan ? An express train crowded with holiday travelers derailed in southern Pakistan on Wednesday, killing at least 58 people and leaving hundreds of terrified survivors to claw their way out of the wreckage in total darkness.

The train, which derailed at about 2 a.m., was loaded with an estimated 900 passengers, many of them heading home for the Islamic holiday of Eid al-Adha.

Dozens of soldiers and police helped tend the injured and carry them away to waiting ambulances, as hundreds of people from the surrounding villages looked on. Army engineers used two cranes and cutting equipment to free the last survivors.

The train was speeding from Karachi toward Lahore when about 12 of its 16 carriages came off the rails near Mehrabpur, about 250 miles north of Karachi. It was unclear what caused the accident.