Indian police said someone might have tampered with signals to sabotage the trains which collided early Monday morning in the eastern Indian state of West Bengal, in which 60 people were killed, reported local TV CNN-IBN.
The tragedy happened as a speeding passenger train hit from behind another stationary passenger train in another major rail accident in two months in the eastern India.
The Kolkata-bound Uttarbanga Express overshot the track signal and rammed into a stationary Bhagalpur-Ranchi Vananchal Express from behind at Sainthia station in the state's Virbhum district some 200 km from Kolkata early Monday.