Sao Paulo, Brazil ? One of Brazil’s most notorious gangs staged dozens of attacks on police before dawn Saturday, setting off gunbattles in three cities that killed at least 30 people, officials said. Twenty-four prison uprisings also were reported across Sao Paulo state.

It was the worst assault on authority since gangsters armed with machine guns, bombs and other weapons attacked police stations in Sao Paulo city over a 10-day stretch of November 2003. That spree also was blamed on the gang First Capital Command, which is known by its Portuguese initials, PCC.

The attacks that began late Friday “were obviously the work of the PCC,” said Enio Lucciola, press spokesman for the Sao Paulo State Public Safety Department.

“It is trying to undermine our authority and intimidate us and the population at large at a time when we have redoubled our efforts to destroy the organization,” Lucciola said by telephone.

Public Safety Secretary Saulo de Castro Abreu said police stations, patrol cars and bars frequented by off-duty officers were attacked in Sao Paulo and three suburbs. Stations in the coastal cities of Cubatao and Guaruja, 50 miles to the southeast, also were attacked.

Abreu said there were 55 separate attacks that killed at least 23 policemen, the girlfriend of one officer, a passer-by and five or six suspected gang members. Thirty-two people – 15 policemen, 15 attackers and two passers-by – were wounded, he said. At least 16 people were arrested.

He said the PCC was trying to intimidate police and government officials as well as retaliate for several of the gang’s jailed leaders being put into solitary confinement, which is one of the ways officials use to break the chain of command with gang members outside the prison.