Sri Lanka deployed hundreds of troops and elite commandos on Sunday after a riot at an overcrowded prison left an inmate dead and six others wounded.
Inmates at Mahara Prison, located just outside the capital Colombo, destroyed the kitchen, the hospital, a newly built rehabilitation building, and vocational training facilities on Saturday.
Deputy Police Inspector-General Sanjeewa Medawatte said the situation was brought under control after reinforcements from the armed forces restored order and returned inmates to their cells.
Mahara Prison housed 4,100 inmates, roughly four times its intended capacity, highlighting a widespread issue across the country's jail system.
The latest unrest came almost a month after another prison riot in the region, in which 10 guards and 21 inmates were killed.