Brazil's Rio de Janeiro tense as police close in on slum gang

Police positioned armored vehicles on the edge of a Rio de Janeiro slum at dusk on Saturday in preparation for a possible offensive to root out drug traffickers behind a wave of urban violence that has killed at least 46 people.                                           

A cordon of more than 1,000 police and army officers sealed off the Alemao slum, or favela, as part of an unusually determined effort by security forces to take control of territory that has long been controlled by drug gangs. 

Police said early on Saturday that suspected traffickers should give themselves up while they had the chance. As night fell, armored police vehicles were positioning themselves inside of the slum's outer limits.                                           

"There is not the slightest chance traffickers can win in this war in Alemao," Sergio Duarte, head of the military police, told reporters, referring to the surrounded shantytown.                                           

Authorities have cast the battle as part of a larger effort to stamp out violence in the city ahead of the Olympic Games in 2016. Drug gangs have fought back by setting fire to around 100 cars and buses and firing on police with automatic weapons.                                           

"We are in position to invade Alemao at any moment. It's better they give themselves in now and bring their weapons while there's still time, because when we invade, it's going to be more difficult," Duarte said early on Saturday. 

Police stationed a secure truck at a street on the edge of the favela to bring in gang members who surrendered. Police said they had caught at least 15 people who tried to break through the cordon, including two suspected gang leaders.  

Suspected traffickers fled to Alemao from the Vila Cruzeiro slum after police invaded it earlier this week and took control. Local media say officers have since found guns and grenades there and a machine to count bank notes from the traffickers' lucrative illegal trade.                                           

Large numbers of poor live in Rio's sprawling hillside favelas, making it harder for police to hunt down the gangs. Many innocent slum-dwellers have been killed over the years in the cross fire of gun battles between gangs and police.                                           

A 14-year-old girl was killed by a stray bullet during the Vila Cruzeiro invasion.                                           

Local media said some fearful favela residents have hung white flags outside their ramshackle brick homes.                                           

Police search vehicles and pedestrians entering Alemao. Gang members inside the slum have opened fire on the security forces to try to ward them off, injuring 10 people on Friday and Saturday, including a Reuters photographer.

The latest wave of violence has cast some doubts over whether the city is safe enough to host the 2014 soccer World Cup and the 2016 Olympics, even though sports authorities have said they trust the government's security measures.