SAO PAULO, May 13: Gang attacks on Brazilian police in and around Sao Paulo left 21 people dead and 32 wounded on Saturday in the worst outbreak of violence in the greater metropolis in years.

“The police will not retreat from these attacks,” Saulo de Abreu, the Secretary of Security of Sao Paulo state, told Globo News TV. “They have struck at the spinal cord ... of our security.”

A spokesman at the secretary said the roughly 12 hours of attacks with machine guns and grenades were believed to be related to a transfer in the jails of organized crime leaders of the First Command Capital, know as the PCC in Portuguese.

The leaders were being transferred in an attempt to foil a coordinated rebellion in various prisons across Sao Paulo state planned for the Mothers Day weekend.

Two prison rebellions in the cities of Iaras and Avare broke out on Friday in Sao Paulo state with over 25 hostages between them, the secretary of penitentiaries said. They are ongoing and officials are negotiating for their end.

The secretary said there were signs that rebellions may have broken out at two other prisons in the state, Araraquara and Ribeirao Preto, but it was waiting for more information.

The prison uprisings are believed to have been organized by the PCC, officials said. In February of 2001, 29 prisons in the state of Sao Paulo simultaneously broke out into revolt, leaving 19 dead.

Thirteen policemen, one penitentiary agent, one civilian and 6 bandits had been killed in attacks. —Reuters