One year after the bloodiest-ever police raid of a favela in Rio de Janeiro’s history, a forceful new operation by Brazilian officers on Tuesday has left 11 people dead including a bystander. Military police said they came under gunfire as they planned to enter a slum called Vila Cruzeiro in the north of the city with the mission of locating and arresting “criminal leaders.” In the ensuing gun battle, 10 alleged criminals died, as did a female resident of the favela who was hit by a stray bullet. Police often carry out raids in Rio’s teeming slums to fight drug trafficking. They said that this time they were looking for gang leaders hiding out in Vila Cruzeiro that were from other parts of Brazil. This was the deadliest police raid in a year in Rio. Last May, a police raid in a favela called Jacarezinho left 28 people dead including a police officer. It was the largest such toll in the city’s history. Vila Cruzeiro, a favela crowded onto a hillside not far from Rio de Janeiro’s international airport, had already been the scene of violent confrontation in February, when police killed eight people. Tuesday’s pre-dawn raid targetted the Comando Vermelho, or Red Command, one of Brazil’s most powerful crime gangs “responsible for more than 80 percent of the shootings in Rio,” a police spokesman told TV Globo.