Nepal (65) was suffering from Tuberculosis, they said.
"His health worsened today and he was immediately rushed to jail hospital. Seeing no improvement in his condition, he was referred to the district hospital where he died despite being immediately put on treatment," police said.
Jail Superintendent Viresh Raj Sharma said that Nepal was arrested by Sahibabad police around five years ago and was booked for his alleged involvement in a forgery and attempt to murder case.