The inmates ran away from the juvenile home here last night by snatching keys of the main gate from the guards, Deputy SP Sanjiv Vajpayee said.
The undertrials also attacked the guards, Vajpayee told PTI.
Security checks have been stepped up across western UP after the incident, police said, adding an inquiry has also been ordered into it.
On March 30, two groups of boys in the home were injured in a clash.