Rio de Janeiro favelas occupied after major operation 6 October 2013 Last updated at 20:53 There was no resistance from gangs to Sunday's operation, authorities said Hundreds of Brazilian security officers, backed by armoured vehicles and helicopters, have occupied 12 shanty towns in Rio de Janeiro. The major operation is part of an ongoing drive by authorities to push drug gangs away from poor areas. Two new police pacification units (UPP) will be set up in Lins de Vasconcellos, home to about 15,000 people. Since 2008, another 34 UPPs have been set up across the state but there have also been reports of police brutality. Rio will host the 2016 Olympics and matches of next year's football World Cup. Step towards peace Hundreds of police officers backed by at least two armoured vehicles and three helicopters moved into the slums at dawn on Sunday. There has been no resistance from gangs on Sunday's operation, authorities say. "This is another step towards peace," Rio state governor Sergio Cabral Filho told reporters. He said the government would now invest $225m (£140m) in public works to improve the living conditions in the area. At least one man was arrested, and guns and drugs were confiscated, police said. Governor Cabral Filho said the pacification programme should reach the Mare area - a series of interlinked shanty towns that are home to more than 130,000 people - until early next year. The occupation of the Mare slums are seen as one of the most challenging yet by Rio authorities. Earlier this year, police also occupied the shanty towns of Complexo do Caju and Barreira do Vasco without trouble. But 10 police officers of a UPP in one of Rio's largest slums, Rocinha, were accused of torturing and killing a resident. Bricklayer Amarildo de Souza disappeared in July and was never seen again. The officers reject the accusations.