Several more people were injured, and officials said the death toll could rise, the Hindustan Times reported.
Two of the dead were children.
Officials said there was no fire on the Alleppey-Dhanbad Express, which was traveling between Kerala state near India's southern tip to Dhanbad near the border of Bangladesh. Passengers responding to a rumor pulled the emergency stop cord and then jumped off into the path of another train.
The accident occurred at around 7 p.m. in Andhra Pradesh state.
Eyewitnesses said bodies were scattered along the tracks, many of them with limbs severed.
India has one of the world's largest rail systems, with more than 70,000 miles of line and 25 million passengers a day. Trains are usually crowded, and there have been many deadly accidents.
A few days ago, 45 people were killed by a bus fire in Andhra Pradesh.
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