The incident came to notice of the jail authorities in the morning at 4.15 am, a police official said.
The jail Superintendent lodged a complaint in Boileauganj police station that three prisoners - Lila Dhar Kharak (22), Pratap Singh (27) and Prem Bahadur (22) - all hailing from Nepal, broke the jail and escaped.
During preliminary investigations, it was found that the inmates managed to escape due to the negligence of the two sentries on the night duty and both have been suspended, jail authorities said.
The prisoners reportedly cut the bars of the cell with a blade, climbed the outer wall with the help of pipes and jumped out of the jail.
Goyal said that the photographs of the prisoners have been flashed, borders have been sealed and frantic search operations are on to nab the prisoners.
Kharak is an accused in a murder case, Singh has been charged with rape of a minor while Bahadur was under arrest in rape cases registered in Rampur, Goyal said.