At least seven people have been killed and about 70 others were held hostage overnight in a prison riot in Brazil.

Brawling inmates, reportedly armed with knives and handguns, held about 70 hostages, including women and children, at the Feira de Santana prison in the state of Bahia in Brazil's northeast from Sunday afternoon until Monday morning.

The hostages were at the prison visiting their families during Sunday afternoon visiting hours when the riot broke out.

It is believed the unrest started with a fight between rival factions in the overcrowded prison in the second largest city of Bahia state.

Outside the prison, family members of inmates and hostages desperately waited to hear news from behind the prison walls.

"I want to know what is happening with my son," one man told the Reuters news agency.

Negotiations

Police and a human rights commission negotiated for the release of the hostages and for an end to the violence.

The inmates finally agreed to let five injured prisoners leave the penitentiary to seek treatment at an area hospital.

But by nightfall there still was no solution to the standoff.

"They're reluctant and we will talk about it tomorrow. We are going to continue to negotiate with them," police chief Adelmario Xavier said.

The hostages were finally released, children and the elderly first, in groups of four on Monday morning.

An investigation is being carried out to see what led to the riot.

News agency the Associated Press said at least seven people died, but Reuters said eight inmates were killed, one of them reportedly decapitated, and at least five others were injured in the violence.

The prison houses 1,467 inmates but is only designed to house 644.

Source: Agencies