Ranger Sadan Kumar of Madanpur forest reserve said that the pachyderm was killed after being run over by a goods train at Delhi camp inside the tiger reserve area last night.
The forest department officials held the driver, co-driver and guard of the train coming from Gorakhpur and kept them at Madanpur range office under Wildlife Act.
They were charged with exceeding the speed limit of train in the reserve area which is fixed at 30 km per hour.
The speed limit of trains plying inside the Balmiki Tiger Reserve is 30 km per hour and honking is prohibited.