The riot, which broke out Sunday afternoon and lasted 17 hours through the night, resulted from a fight in the Anisio Jobim Penitentiary Complex between members of two rival crime organizations -- Primeiro Comando da Capital (PCC), a drug gang based in Sao Paulo and having expanded to other states, and Familia do Norte.
According to a statement by public security officials, the 56 dead appeared to be PCC members. Meanwhile, 184 prisoners were confirmed to have escaped, while around 40 have been caught under an operation, according to the state penitentiary secretariat.
The riot was brought under control by around 7 a.m. AMT (1100 GMT) on Monday, Amazonas Public Security Secretary Sergio Fontes told a press conference.
Fontes said several decapitated bodies were thrown over the prison wall, and most of those killed came from one gang.
"This was another chapter in the silent and ruthless war of drug trafficking," he said.
During the riot, 12 prison wardens were taken hostage, but all of them were released uninjured, according to Epitacio Almeida, representative of the local bar associations Human Rights Commission.
Luis Carlos Valois, judge in Amazonas, who led negotiations with the inmates to end the riot, told Daily O Globo that many of those killed were executed on Sunday.
The daily quoted him as saying that "piles of bodies were scattered along the corridors, severed limbs in the corners and decapitated heads around the place. The floor was awash with blood."
Just as the riot began in one unit, dozens of prisoners in the second unit started a mass escape in what authorities said was a coordinated effort to distract guards. The situation was quickly brought under control.
Brazils prison system is notoriously overcrowded, which has led to several deadly riots in the past.
The Anisio Jobim prison had a capacity of 592 people but actually housed 1,224 prisoners, according to Fontes.
The Amazonas government has decided to move around 130 inmates in order to protect them. Enditem.(*)
Editor: Heru Purwanto
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