Six police said they opened fire in a Rio slum skirmish after which a well-known dancer was found dead, police said Saturday as they probe the incident that caused mass demos.
Violence flared on Tuesday in the city's tourist Copacabana Beach area after the dancer was found shot dead, heightening fears about security in a city that will host seven World Cup games including the July 13 final.
Police will next investigate whether the bullet that killed Douglas Rafael da Silva Pereira, 25, came from a police officer or one of the drug traffickers involved in the skirmish, police were quoted as saying on the news website G1.
The nine officers involved in the shootout all denied shooting the dancer. Their weapons, however, have already undergone a primary evaluation and have not been returned to them, according to commissioner Gilberto Ribeiro.
Officials confirmed Friday that the dancer was found dead and with a shot in the back. Initial reports stated that he fell down.
In addition, a 27-year-old man described as mentally disabled was killed after being shot in the head during the protests over the dancer's death.
Police in recent months have cranked up efforts to clear favelas of violent criminals before the month-long World Cup kicks off on June 12, followed by the Olympics in 2016.
Although a huge slum "pacification" program was launched six years ago to improve security in Rio, the gangs have been fighting back.