The deceased, identified as Ram Kumar, was facing trial in a kidnapping case of Seemapuri area. He was lodged in jail number 8.
"His body was found hanging by a ceiling fan inside the jail around 6 PM. A jail warden saw the body and informed the other officials after which it was rushed to a nearby hospital where the man was declared brought dead," the official said.
A judicial inquiry has been marked and the body has been sent for postmortem while his family has been informed, the officials said.