At least three inmates are reported to have been beheaded and more than 30 have been killed in a riot involving different gangs at a prison in the Brazilian city of Natal.

Violence erupted at the Alcacuz Penitentiary in the north-east of the country after prisoners from one drug gang invaded a block occupied by a rival mob.

The riot continued for around 14 hours before military police entered the prison and restored order. Officials had said they were waiting until dawn before attempting to put a stop to the riot because of reports some inmates were armed.

Officials initially announced that at least ten prisoners have been killed but sources told the G1 news website the current death toll is closer to 25. Reuter's reports that the current death toll stands at 30.

As many as 100 people are feared to have died but authorities will not be able to release a final figure until they have accessed all areas of the prison.

Sources said the violence was part of an on-going battle between two drug gangs: the Crime Syndicate and First Command of the Capital.

Some of the victims are reported to have been decapitated and mutilated.

“We could see the heads ripped off'', prison co-ordinator Zemilton Silva told Folha de Sao Paulo.

As the riot continued, relatives waited outside the prison awaiting news of their loved ones. One inmate was reported to have escaped but has since been recaptured.

Feminist protests demand end to violence against women in Brazil after gang rape of teenage girl Show all 10 1 /10 Feminist protests demand end to violence against women in Brazil after gang rape of teenage girl Feminist protests demand end to violence against women in Brazil after gang rape of teenage girl Brazilian women march in Sao Paulo during a protest following the gang rape of a 16-year-old girl Rex Features Feminist protests demand end to violence against women in Brazil after gang rape of teenage girl There have been calls for protests to end to what campaigners call Brazil's 'culture of rape' after the attack Rex Features Feminist protests demand end to violence against women in Brazil after gang rape of teenage girl An online campaign has been set up in response to the crime, using the hashtag #EstuproNuncaMais, meaning 'rape never again' Rex Features Feminist protests demand end to violence against women in Brazil after gang rape of teenage girl The 16-year-old victim was attacked in a poor neighbourhood in the west of the city on 21 May 2016 Rex Features Feminist protests demand end to violence against women in Brazil after gang rape of teenage girl Two of the attackers posted pictures and video on Twitter of the assault, which has shocked the country Rex Features Feminist protests demand end to violence against women in Brazil after gang rape of teenage girl Brazilian women protest in front of the Candelaria Church in Rio de Janeiro AFP/Getty Images Feminist protests demand end to violence against women in Brazil after gang rape of teenage girl Seven men have been charged in connection with the attack AFP/Getty Images Feminist protests demand end to violence against women in Brazil after gang rape of teenage girl Women's underwear and photos from Brazilian photographer Marcio Freitas displayed on Copacabana beach during a protest by non-governmental organization Rio de Paz (Rio of Peace) against rape and violence against women REUTERS Feminist protests demand end to violence against women in Brazil after gang rape of teenage girl Women's underwear smeared with paint is seen during a protest against rape and violence against women in Brasilia, Brazil REUTERS Feminist protests demand end to violence against women in Brazil after gang rape of teenage girl Demonstrators attend a protest against rape and violence against women in Brasilia, Brazil REUTERS

There have been a number of riots in Brazilian prisons in recent weeks. At least 116 prisoners have been murdered in Brazil in 2017 and that death toll is expected to rise after the latest riot.

Following the latest violence, Alexandre de Moraes, Brazil’s Justice Minister, admitted the prison system had become “a barrel of gunpowder”.