The operation was launched at 5:00 am (0800 GMT) in Niteroi, across the Bay of Guanabara from Rio, which hosted the Olympics exactly a year ago but is now in the grip of a crime wave.
“The civil and military police, supported by the armed forces, launched a public security operation at dawn today,” the Rio state security office said in a statement.
Officials said the army, called in last month by President Michel Temer to prop up the struggling police force, was “responsible for perimeters in some communities in the region and is stationed at strategic points.”
The soldiers in camouflage and wearing helmets patrolled on foot, supported by armored personnel carriers and other hardware.
According to Globo news, 2,600 personnel, including marines, were involved in the raid to help police serve 26 arrest warrants and conduct 34 searches. The action was focused on favelas in Niteroi where crime gangs have turned large areas into almost no-go areas for the authorities.
Globo reported that one soldier had been wounded by gunfire, but this was not immediately confirmed by officials.
Earlier this month, a similar operation, involving about 5,000 soldiers and police, was carried out in northern Rio to try to clamp down on gangs responsible for a wave of truck hijackings. Two suspects were killed that day.
Rio was the first South American city to host the Olympics.
The event passed off smoothly, but a mixture of corruption scandals, near collapse in the state budget and crime has combined into a serious hangover for what should be one of Brazil’s richest regions.
In the first half of this year Rio tallied 3,457 homicides — the highest level of violence since 2009 and 15 percent more than during the same period in 2016.
So far this year 97 policeman have been killed in the state.
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