Seven staff members of Aligarh district jail were among the nine persons injured on Friday following violence over the confiscation of a mobile from a prisoner, officials said.
Deputy jailer R P Choudhary was also injured in the brick batting by unruly prisoners. The trouble started after jail officials confiscated mobile phone from a prisoner serving a life term, Additional district Magistrate city, Shailender Singh told PTI.
Angered by this, a group of hardened criminals instigated other prisoners who demolished a brick structure inside the jail complex and used the debris for attacking the jail staff, officials said, adding senior district and police officials rushed to the spot and managed to diffuse the situation.
City Superintendent of Police Mansingh Chouhan said the situation was "under control".