A massive police raid targeting a drug-trafficking gang in Rio de Janeiro left at least 121 people dead, authorities said Thursday morning.

The operation began Tuesday in two of the city’s favelas, sparking intense gun battles. An unknown number of people were wounded. Among the dead were four police officers, according to officials.

Human rights organizations have called for investigations into the deaths, describing the operation as one of the most violent in Brazil’s recent history.

Police said the raid followed a yearlong investigation into the Red Command, a criminal gang that controls drug trafficking and other illicit activities in the low-income communities of Complexo do Alemao and Penha. The group originated in Rio’s prison system and has expanded its influence in recent years.

During the operation, officers arrested 113 people, seized 118 weapons and confiscated more than a ton of drugs, police said.

The violence disrupted daily life in the affected neighborhoods. Schools closed, a local university canceled classes, and buses were used to block roads.

Rio has long been the scene of deadly police raids. In March 2005, 29 people were killed in the Baixada Fluminense region, which borders Rio. In May 2021, 28 died in a raid in the Jacarezinho favela.

However, the scale of Tuesday’s operation was unprecedented. The action sparked protests and accusations of excessive force and calls for the resignation of Rio’s governor.

On Thursday morning, community leaders in Penha gathered at the headquarters of the favela rights group CUFA to prepare legal support for grieving families. Many shops remained closed, and the atmosphere was still somber.

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Gabriela Sá Pessoa reported from Sao Paulo.

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