At least 64 people have died in a massive police raid aimed at organized crime in Rio de Janeiro on Tuesday, security officials told CNN Brasil. Among the dead are four Brazilian police officers, officials added.

Rio de Janeiro State Governor Cláudio Castro told reporters at a press conference that police confiscated a “large quantity of drugs” in the raid, according to Reuters. Authorities also claimed on social media that at least 42 rifles were seized during the operation.

In a post on X on Tuesday afternoon, Castro pronounced the raid “the biggest operation in the history of Rio de Janeiro.”

Police raids are common in the city before international events, and next week, Rio will host a major climate conference, the C40 World Mayors Summit.

Video published by Reuters on Tuesday showed huge columns of black smoke emerging from the Alemão favela during the raid. Photographs of Alemão in the aftermath showed the source: burned cars, constructed as barricades.

Authorities launched an operation aiming to “combat the territorial expansion” of the Comando Vermelho criminal group, Rio de Janeiro’s government added in a lengthy thread on X.

The operation was in the works for over a year, the government said, and involved more than 2,500 military and civilian police personnel.

Comando Vermelho is Brazil’s oldest active criminal organization, according to the think tank InSight Crime. Its name, Portuguese for “Red Command,” is a reference to its origins as a leftist prisoners’ organization formed during the military dictatorship that ruled over Brazil until 1985.

Since then, Red Command has become a massive, transnational criminal group, involved in drug trafficking and extortion. InSight Crime reports that in recent years, it has struggled with escalating violence from the state and other criminal militias.

Gang used drones, police claim

At least 81 people were arrested Tuesday, according to a social media post by Rio de Janeiro’s Police Department.

Cars burnt during a barricade within the Operacao Contencao (Operation Containment) at the Vila Cruzeiro favela, in the Penha complex, in Rio de Janeiro, Brazil, on Tuesday. Mauro Pimentel/AFP/Getty Images

People react while waiting for news outside a hospital on the day of a police operation against drug trafficking in Rio de Janeiro, Brazil, on Tuesday. Aline Massuca/Reuters

During the raid, gang members allegedly targeted police with a drone, authorities said.

“In retaliation, criminals used drones to attack police officers in the Penha Complex,” Rio de Janeiro’s state government said in a post on X, sharing a video of what appears to show a drone firing a projectile from the sky.

“Despite the attacks, security forces remain steadfast in the fight against crime,” the state government added.

“This is the magnitude of the challenge we face,” Castro said in a post, before using a term popular among tough-on-crime leaders in the United States and Latin America. “It is no longer a common crime; it is narco-terrorism.”

Castro also asked residents of the affected neighborhoods to remain indoors while the operation is underway.

The US State Department told visitors to steer clear of northern Rio on Tuesday, warning that “ongoing fighting between police and criminal factions have caused disruptions to traffic in multiple areas of the North Zone.”

UN human rights office ‘horrified’

Tuesday’s raid is not the first in the Alemão favela this year. In January, a police operation ended with five dead and the neighborhood littered with similar barricades of burned-out cars.

On Tuesday, Rio de Janeiro’s governor claimed the operation in Alemão was larger than an infamous, protracted security crisis the neighborhood experienced in 2010.

According to the Fogo Cruzado (Crossfire) Institute, which tracks gun violence in Brazil, more than half of the firearms injuries recorded in September 2025 came from police operations.

Past raids on similar slums in Brazil have attracted copious criticism from civil rights advocates. In May 2021, a raid in the Jacarezinho favela killed at least 25 people and led the Supreme Court to ban all police raids until the end of the COVID pandemic unless the circumstances were “absolutely exceptional.”

On Tuesday, the United Nations Human Rights Office criticized the raid in a post on X, saying that it was “horrified” by the scale of the violence.

“This deadly operation furthers the trend of extreme lethal consequences of police operations in Brazil’s marginalized communities,” the office wrote. “We remind authorities of their obligations under international human rights law, and urge prompt and effective investigations.”