More than 50 people have been killed after intense, hours-long violence broke out in a prison in Para, Brazil. Officials say 16 of the dead were decapitated as rival prison gangs fought.

Extremely graphic footage shared online purportedly filmed inside the prison shows men kicking and tossing several severed heads around as bodies lie prone nearby. Other footage shows part of the prison in flames.

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Fighting broke out in the Altamira Regional Recovery Center around 7am local time when the members of one gang invaded an area occupied by a rival group, an official from the Para state government’s penitentiary department said.

Rebelião em Altamira PA agentes penitenciários feitos de refém segundo a reportagem de Felipe Adams pic.twitter.com/7KSqlYnkXG — Adriano Direitasso (@Adriano04000013) July 29, 2019

Inmates then set the area alight in retaliation, and two prison officers were taken hostage. The hostages were released after negotiations, and the riot lasted about five hours. Military police are still on the scene.

“We have 52 dead, including 16 beheaded. It is still very hot inside the prison, and we are working to remove bodies,”said state penitentiary official Jarbas Vasconcelos Carmo.

Presos fazem motim em cadeia pública de Altamira PA....... pic.twitter.com/Kxx2KQdUfc — Pará Notícias (@Paranoticias1) July 29, 2019

Brazil’s prisons are notoriously overcrowded. According to official figures, the Altamira facility in Para has a capacity of 208 inmates but had 372 detainees when violence broke out Monday.

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