The official inquiry concluded that the derailment was caused by one pillar of the 140-year old bridge sinking into the riverbed, following recent heavy rain, though this finding has been challenged.
[2][3] The death toll rose steadily as bodies were retrieved from the wreckage over the course of a week, 59 people were eventually reported as dead or missing,[2] including at least eight women and two children, whilst between 117 and 300 were injured and transported to nearby hospitals.
The bridge was 140 years old and in a poor state of repair, and it shifted when the line broke, derailing six cars of the train.
Support was also received from fire brigades and the Indian Navy, who sent fifty professional divers to attempt to rescue those trapped in the underwater railway cars.
Subsequent private investigations have challenged this theory, pointing out that the bridge is damaged on top of the structure in a way which would not be possible if the pillar was unstable.