At least 20 people, including two police officers, were killed in a large-scale operation against organized crime in Rio de Janeiro on Tuesday, days before the Brazilian city is set to host major events related to the COP30 global climate summit.
"We stand firm confronting narcoterrorism," Governor Claudio Castro wrote on social media as he announced the operation, which he said involved 2,500 security personnel across the Alemao and Penha favela complexes.
The complexes are poor, densely populated settlements on Rio's outskirts.
Authorities said the other 18 fatalities were suspected of connections to drug trafficking.
Rio next week will host the C40 summit of global mayors and Prince William's Earthshot Prize, which will feature celebrities including pop star Kylie Minogue and four-time Formula One world champion Sebastian Vettel.
Both are part of the runup to the United Nations climate summit COP30 taking place in Belem, in northern Brazil.
Large-scale police operations are not uncommon ahead of major international events in Rio, which hosted matches of the 2014 World Cup, the 2016 Olympics, the 2024 G20 summit, and the BRICS summit earlier this year.
Tuesday's operation was described by the state government as the largest ever targeting the Comando Vermelho gang.
At least 56 people have been arrested as authorities sought to serve 250 arrest and search warrants, the government added.

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