The goods train that on Thursday run over the pregnant wild elephant on the Dooars railway tracks in Jalpaiguri district had to be speeding, given the nature of injuries revealed in the post-mortem, a senior official of state forest department said on Saturday.

The train's loco had rammed into the elephant when it was crossing the tracks in Chapramari Wildlife Sanctuary area of the district's Nagrakata block. The impact ripped apart the elephant's abdomen and a full-grown foetus came out, which met the same fate as its mother.

Railway officials had claimed that the train was running at around 20kmph to 30kmph.

Dwijapratim Sen, the divisional forest officer of Gorumara wildlife division, said the extent of the elephant's injuries pointed to the train's speeding. “During the post-mortem, our vets found eight ribs of the elephant had fractured and the carcass of the foetus mutilated. They are of the opinion that the train could not have been running at 20-30kmph, but faster, or else, the elephant would not have suffered such extensive injuries," Sen said.

Foresters have filed a general diary and have sought records of the train's speed.