8 dead in second prison riot - police

Eight inmates were killed and burned Monday in a fresh prison riot in Brazil, police said, a day after clashes between rival factions in another jail left 25 detainees dead.

"There are thought to be eight people dead but the bodies are burned and the medical authorities will have to confirm" the toll, a local police spokesman told AFP after Monday's riot at a jail in the northwestern state of Rondonia.

It was the latest eruption of gruesome violence to hit the country's underfunded and overcrowded prison system.

Police said the Rondonia riot was thought to be linked to one on Sunday in the far northern state of Roraima, where 25 inmates were killed and women visitors taken hostage.

In the first riot in the Roraima state capital Boa Vista, seven of the dead were beheaded and six burned to death, the news site G1 reported, citing local police.

Human rights groups have long complained about the deplorable conditions in Brazilian prisons, where fights and riots are frequent amid overcrowding.

At the end of 2014, there were 622,000 people imprisoned in Brazil, according to a Ministry of Justice report, which added that most of the prisoners are black males.

Brazil has the world's fourth-largest prison population, after the United States, China and Russia, the report said.