A Rajasthan Police constable allegedly committed suicide by jumping in front of a train in the Jhotwara area on Tuesday, police said.
The incident occurred in the early hours, they added.
The deceased has been identified as Ajay Singh Chaudhary. He was attached to the police lines.
A suicide note was recovered from the spot in which Mr Chaudhary had stated that no one was responsible for his taking the extreme step, police said.
The body has been handed over to family members after post-mortem, they said.
Police said the matter is being probed.
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