Brazilian police say about 2000 officers met no major resistance when carrying out the planned occupation of a complex of shantytowns long held by Rio de Janeiro's largest drug-dealing faction.
Police said in a release that the Sunday morning (local time) operation took about 20 minutes. In the Jacarezinho slum, six shots were fired once police arrived, and one suspect was injured while trying to set fire to a barricade meant to keep officers out.
The operation started at dawn and the Brazilian and the state flags were raised in the centre of the complex by 10am.
This area will now become part of a state programme that establishes so-called "peacekeeping police units" in shantytowns previously held by drug traffickers. This is the 29th such unit in Rio de Janeiro.
The introduction of the peacekeeping programme in the region is part of efforts to crack down on crime and increase security as the city prepares to host the 2014 football World Cup and the 2016 Olympic Games.