At least 25 people, including four prison guards, were killed and more than 100 injured in two days of riots at Negombo Prison in western Sri Lanka. The violence, which began with clashes between inmate groups, is reported to be the worst prison unrest in the country in years.

The unrest started Sunday with altercations between prisoners, leading to two deaths and dozens of injuries. Inmates are alleged to have obtained prison weapons during this initial phase. Later that day, male prisoners and individuals from an adjacent female unit climbed onto prison rooftops, demanding their release.

Fresh violence erupted on Monday when inmates attempted to breach the prison gates. Security forces were deployed, and multiple gunshots were heard from within the facility. The conflict was reportedly triggered by an inmate informing on a drug trafficking operation within the prison.

Some of the injured were transported to Negombo Hospital, where the director told AFP that some sustained bullet wounds while others suffered cuts and severe bruises. Additional wounded individuals were taken to Colombo National Hospital. According to AFP, a portion of the prison's roof collapsed during the incident, injuring some women.

A member of the army stands in front of a yellow barrier - a building with the words Sri Lanka prison is in the background. Four other personnel are behind him, one facing the same way

Relatives of inmates gathered outside the prison on Monday as the situation unfolded. Some told BBC Sinhala that they had not received information regarding the whereabouts or fate of their relatives.