India Train Wreck: Cause of Deadly Accident Uncovered.

A signal error caused a train derailment in India that killed at least 275 people and injured hundreds more. One of the trains had been given a signal to run on an already-occupied line, which caused it to ram into a freight train carrying iron ore. After the collision, the passenger train fell onto another set of tracks, where it collided with another train carrying more than 2,000 people. Sabotage has not been ruled out.