An inmate was killed and three others were injured when prison officials opened fire to control a tense situation erupted at the Mahara Prison this evening, Police Spokesperson DIG Ajith Rohana said. He said the injured inmates were hospitalised. “We have sent four police teams headed by SSP Kelaniya and OIC Ragama to control the situation and teams of STF personnel to provide security to the outer perimeter of the prison,” the DIG said.