Brazilian police on Sunday moved to occupy slums near Rio de Janeiro's international airport and seaport as part of efforts to drive out drug traffickers ahead of the 2014 World Cup.
The operation, which began at 4:55 am local time (0755 GMT), involved hundreds of police backed by mechanized units of the military, which entered the favelas of Caju and Barreira do Vasco and began establishing control of their narrow streets.
There was no immediate reports of resistance from residents of the township.
Officials said earlier that more than 1,000 police and 200 navy commandos in armored vehicles had planned to take part in the operation.
According to police, their next target would be violence-plagued Mare, an area near the airport largely controlled by drug gangs and militia units.
The area, home to 75,000 people, is ringed by freeways, including one that provides access to Galeao international airport.
Rio's feared military police battalion BOPE are to occupy the zone until a specially-trained police force known as UPP can be deployed.
In 2008, Rio authorities moved to reassert control in lawless favelas, or slums, ahead of the 2014 World Cup and the 2016 Rio summer Olympics.
So far, 30 UPPs (Police Pacification Units) with more than 8,000 officers have been deployed and are protecting more than half of the two million people who live in local slums.
Authorities said their goal is to have 40 UPPs in place by 2014.
Violence has receded since police launched operations in the slums, including in Rocinha, Brazil's largest shantytown.
In the first half of 2012 the murder rate fell to 10.9 per 100,000 residents, far lower than the national average of 26 per 100,000.
In 2009, the murder rate in Rio was 36.2 per 100,000 inhabitants.