Police mount the raid in Rio de Janeiro
At least 10 people have been killed after Brazilian police raided shanty towns in Rio de Janeiro in an anti-drugs operation.
About 300 police and special forces using armoured vehicles and helicopters descended upon four slums, know as favelas, in the west of the city.
Police say all those who died were suspected drug dealers.
But a BBC correspondent in the city says community groups often challenge the police version of events.
The operation comes as officials recently launched a new approach to ridding the favelas of drugs traffickers.
Instead of withdrawing after violent shootouts, police aim to maintain a constant presence in the shanty towns.
Police said the target of the latest operation had been drugs, arms and stolen cars in the sprawling favelas.
Those killed included two teenage boys, the city's civil defence ministry confirmed.
At least seven people were arrested and police say they recovered guns, two grenades and an assortment of drugs.
A woman who was hit by a stray bullet was also taken to hospital, reports say.
"It was a success. With today's operation we have considerably weakened the criminals," said the head of civil police, Gilberto Ribeiro.
Police often stay out of Rio's large shanty towns, only entering on heavily armed raids directed against drug gangs or illegal militias, says the BBC's Gary Duffy in Rio de Janeiro.
However a new approach to policing is being tried in two poor neighbourhoods, one of which was visited by Brazil's President Luiz Inacio Lula da Silva on Tuesday.
Police are maintaining a 24-hour presence in the shanty town of Santa Marta to try to reclaim the area from drugs gangs.
Analysts say the experiment might offer at least a limited alternative for policing in city.
However there are more than 900 shanty towns and the costs and challenges of ensuring all are properly policed would be enormous, our correspondent says.