Brazilian authorities said they put down at least 11 weekend prison riots that killed three inmates and injured 20 guards and prisoners in the first outbreak of riots since inmates launched a wave of violence that shocked Sao Paolo last month.

Alcides da Silva, head of the union of Sao Paulo state prison guards, said at least one rebellion was started by the First Capital Command, or PCC, the same feared gang that initiated a week of street violence and prison uprisings last month that killed almost 200 people across Sao Paulo state.

Three prisoners were killed in the new uprisings, one of them decapitated, as inmates in control of the lockups settled scores, the Agencia Estado news service and the Web site of Folha de S. Paulo newspaper reported Sunday.

Television footage also showed inmates beating a guard in a prison, then suspending him with makeshift ropes fashioned from bed sheets over the edge of a 40-foot-high wall.

The reports said about 20 guards and inmates suffered unspecified injuries after riot police were deployed to the prisons in the states of Sao Paulo and Espirito Santo, north of Rio de Janeiro.

Sao Paulo's state government said in a statement that the rebellions were over and that 19 hostages had been freed, but did not provide more details.

The government of Espirito Santo said elite federal police were called in to help restore order inside the prisons, but did not provide details about how the institutions were brought back under control. Prison officials in both states did not return repeated telephone messages seeking comment.

The riots came just over a month after jailed leaders of the PCC allegedly launched a wave of attacks on police in Sao Paulo, enraged by a move on May 11 to transfer gang leaders to more secure prisons. The gang allegedly ordered attacks the next day that left 41 officers and prison guards dead.

Police struck back, killing 123 people, many described as gang members, though human rights advocates said they suspected police death squads shot innocents as well. Twenty-three inmates also died in the prison rebellions.

The gangs, originally formed in the 1990s to pressure for improved prison conditions, quickly began using their power inside prisons to direct drug and arms trafficking, bank holdups, kidnappings, extortion and killings on the outside.

There are no official numbers on the gang's size, with estimates ranging from 10,000 to 100,000. A gang leader told Brazilian lawmakers this month that the PCC exerts influence over 95 percent of the 140,000 inmates in Sao Paulo state.