A raid of Rio de Janeiro's largest complex of favelas that left at least 18 people dead has sparked renewed complaints of excessive police violence in Brazil and ignited debate over how to handle crime ahead of state and presidential elections.

Residents of Complexo do Alemão protested against the police operation on July 21, alleging excessive force and police violence. The process aimed to locate and arrest criminal leaders, some of whom were from other states, police said in an earlier statement. Rio authorities said 16 suspected criminals were killed in confrontations with police, along with a police officer and a woman.

Earlier this year, Brazil's Supreme Court established a series of conditions for police to conduct raids in Rio's favelas to reduce police killings and violations of human rights. The court ordered that lethal force be used only when all other means have been exhausted and when necessary to protect life.

The ruling came in response to a raid on the Jacarezinho favela in 2021 that resulted in 28 people being killed.