A top forest official said that a tiger was run over by a train in a rare accident in eastern India.
"It is a very rare case, but this has happened," said Manindra Biswas, district forest officer of Kochbihar district of West Bengal state.
Alerted by villagers, forest guards reached the site Monday and took the body of nearly 10-year-old tiger for autopsy, Biswas said.
The body was found on the side of a river bridge, Biswas said, suggesting that the big cat was trying to cross the bridge over a rain-fed river when it was hit by the train.
The area is nearly 700 kilometers (435 miles) north of Calcutta, the capital of West Bengal state, and borders Bangladesh.
A 30-year-old elephant was killed by a train in nearby Jalpaiguri district in April.
Poaching and a vanishing habitat have savaged India's tiger population.
Preliminary results of a recent exhaustive study of tiger habitats found that the tiger population in some Indian states may be nearly 65 percent less than experts had thought.
Conservationists said the early results indicated the most recent tiger census - which found about 3,500 tigers - was far too optimistic. The study was conducted over the past two years by the government-run Wildlife Institute of India.