The death toll in gang violence in Brazil's business capital, Sao Paulo, earlier this month was put at 187 on Friday, 35 higher than previously reported.

A public bus burns after being torched by gangsters, as the unprecedented wave of violence went into its third day, in the eastern district of Sao Paulo May 15, 2006. Heavily armed gangsters attacked police posts, banks and public buses around Sao Paulo State for a third night, as the death toll passed 80, the state security office said on Monday. [Reuters]

The city's Attorney General's Office said the dead included 123 suspected gangsters and 23 prisoners as well as 31 policemen and seven other public officials.

Human rights groups have expressed concern that police used excessive force and that innocent people were executed in retaliation for killings of officers by gang members, including those from the First Command of the Capital, or PCC, gang.

The violence between May 12 and 19 followed the transfer of gang leaders and members to a remote high-security prison and created panic in the world's third-largest metropolis with a population of more than 20 million.

Brazilian newspapers have described the police response as "massacres" and reported that visits to mortuaries showed many of the victims were shot in the head.

On Friday, the head of Sao Paulo's prison service, Nagashi Furukawa, resigned citing "personal reasons" amid media reports of disagreement with the state's public security chief.