Rio De Janeiro: Police launched a major operation in Rio`s favelas on Tuesday, leaving six people dead and four wounded with the World Cup just four months away.
Police moved into five favelas after a policewoman was shot to death in an attack on a police pacification unit.
A unit backed by an armored vehicle entered the Morro do Juramento favela north of Rio after discovering the vehicle used in Sunday`s attack, police lieutenant-colonel Carlos Leal Gomes said.
Globo daily quoted Gomes as saying police had also carried out dawn raids on four other favelas.
Those injured in the confrontations were taken to hospital but local health officials said the four, who included two policemen, had not been seriously hurt.
One person was arrested in the Morro do Juramento operation which turned up four shotguns, two pistols, grenades and a stash of drugs, Gomes said.
He said nine more people were arrested in the other favelas, where a similar haul of weapons and drugs was uncovered.
Over the past week, drug traffickers from the Penha and Complexo do Alemao favelas have been attacking police in "pacification" units tasked with keeping order in Rio`s densely populated hillside slums.
Police have responded but their operations underline the scale of the challenge facing Brazilian authorities, who vowed to crack down on lawlessness in the favelas ahead of June`s World Cup and the 2016 Olympic Games.
More than 600,000 police serving in 38 pacification units have gone into 174 favelas in an operation which started six years ago.
