The failure of the authorities in the state of Rio de Janeiro to combat the huge problem of police killing people in anti-crime operations is sabotaging efforts to improve security, according to a report released by Human Rights Watch on Thursday.
This is the latest in a series of blows to Rio's image with less than a month to go until the Brazilian city hosts the 2016 Olympic Games, ranging from fears over Zika to the fallout from the nation's political turmoil.
The damming 109-page report says police in Rio de Janeiro state killed nearly two people per day in 2015, and many of them extrajudicially.
The New York based group's report included interviews with 34 current and former police officers who detailed a "culture of combat" that they say rewards killing rather than arresting suspects.
"We considered that an operation was successful if it had dead criminals," Major Roberto Valente, who commands a Pacifying Police Unit (UPP) — a military police station in a favela — told Human Rights Watch in December last year.
The report claims many killed by police were in custody, unarmed, or trying to flee. Although Brazilian authorities claim that in most cases the police came under attack, Human Rights Watch studied 64 cases and found inconsistencies with the forensic evidence in half. Autopsies showed the dead in 20 of those cases were shot at close range, which tends not to be common in shootouts.
Officers interviewed also revealed how they had covered up extrajudicial murders in a variety of ways, from planting guns on suspects to removing victims from crime scenes, and destroying evidence.
Police killings are rising as well. In 2015, police killed 645 people compared to 416 in 2013.
This rising murder rate has also disproportionately affected black Brazilians who make up 52 percent of the state's population but 77 percent of those killed by police. While 47 percent of the population is white, it makes up only 15 percent of those killed.
The rate of 3.9 police killings per 100,000 people in 2015 is nearly ten times that of the U.S.
Security has been a hot button issue ahead of the games. Late last month police officers, firefighters, and paramedics protested at Rio's airport over late paychecks and poor working conditions.
They held a banner written in English that said "Welcome to Hell… Whoever comes to Rio de Janeiro won't be safe."
Related: 'Welcome to Hell': Rio police greet visitors five weeks before the Olympics
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