A 45-year-old man was found dead on Wednesday in police custody in Bihar's Rohtas district, a senior official said.
Shrikant Singh allegedly hanged himself from the ceiling of the lockup of Indrapuri police station with his shirt and shoe laces, Additional Superintendent of Police Sanjay Kumar said.
Shrikant Singh was arrested on Tuesday night in connection with the theft of a tractor, along with his son Abhishek, who was later let off as he was a minor, the police officer said.
Meanwhile, Shrikant Singh's wife Reena Devi alleged he was tortured to death.
"I was called to the police station in the early hours under the pretext of some paper work and informed about the death of my husband. I think he was tortured to death," she said.
Shrikant Singh's body has been sent for post-mortem.
"We will take necessary action if any complaint is registered by the bereaved family members," the Additional SP added.