"Nothing can be ruled out. It may be possible that our equipment might have been tampered with. It will be known only after inquiry," Eastern Railways General Manager V.N. Tripathy said here.
"The toll may rise as some are still battling for life in hospital," he added.
This the second time in less than two months for a heavy killer train accident to have taken place in West Bengal.
On May 28, a passenger train derailed and was hit by a cargo train, killing some 150 people.
Authorities blame extreme left-wing Naxal rebels for sabotaging tracks at that time, but the rebels have denied.