Inmates rioting for better facilities in a Brazilian jail have killed four fellow prisoners, decapitating two of them, and have taken two guards hostage, officials have said.

Elson Faxina, a state judicial spokesman, said on Sunday that negotiations to resolve the standoff were to resume on Monday, with 60 percent of the jail still under inmate control overnight.

"A group of prisoners took six inmates hostage; they killed four and have injured two. They also took hostage two guards," said Faxina. "Their demands are about facilities; it is an older building and they want food brought in."

Officials have cut water and electricity to the enclosure, Faxina added, saying police officers were guarding the prison to stop the riot from spreading.

Prisoners set some objects on fire and were using metal poles to cause damage to the 928-bed prison that housed more than 1,000 inmates at the time.

Al Jazeera's Gabriel Elizondo reported from Brazil that more than 100 prisoners, who were not taking part in the riot, were transferred to other jails on Sunday for their safety.

Dozens of the prisoners climbed onto the building's rooftop, with their faces covered with white fabric.

Local media images showed at least 30 rebellious inmates shouting while they beat men held with ropes around their necks, or whose hands were tied behind them.

The rioting inmates waved banners emblazoned with the initials ‘PCC’ for a criminal prison gang formed in the 1990s.

Jairo Ferreira, a lawyer for the prison guards' union, told local news site CGN that at one point the inmates put the decapitated head of one victim on the lap of a custodian who was initially held hostage and later freed.

Relatives arriving at the prison to visit inmates waited outside as night fell, trying to get information about their loved ones.