"We think more than 50 people are still trapped inside. Most are inside S3 and S4 coaches," said a rescue official from the accident site near Jhargram, 155 km from Kolkata.

Soldiers and railway workers used gas cutters to slit open the badly damaged coaches of the train and access the people inside.

The engine and 13 coaches of the Howrah-Kurla Lokmanya Tilak Gyaneshwari Deluxe Express derailed at 1.30 a.m. A good train then smashed into the fallen coaches.

At least 65 people were killed and over 200 injured in the accident, which occurred after suspected Maoists removed 1.5 ft of the track and fishplates.