The three-train collision is India’s worst train crash in two decades|@RailMinIndia|via Twitter

A signal error led to the deadly three-train crash in the Indian state of Odisha that killed more than 280 people and injured more than 1,100, officials said.

The system wrongly directed a passenger train onto a loop track by the side of the main line that made it collide with a freight train derailing cars over to another track. These derailed carriages caused a second passenger train, passing in the opposite direction, to come off the track, causing the nation’s worst train crash in two decades.