RIO DE JANEIRO // At least 23 people have been killed in five days of clashes as Brazilian security forces seek crush drug gangs and impose the law in the violent slums of Rio de Janeiro.
The gangs are fighting back by opening fire on police stations and setting cars and busses ablaze, police said.
Police have deployed armored vehicles, helicopters and thousands of heavily armed agents for the widespread crackdown in the slums, known here as favelas.
Rio authorities are seeking to impose the law in the favelas ahead of hosting of two of the planet's largest sporting events, the World Cup in 2014 and the Olympics two years later.
According to police, two factions of drug dealers have joined forces seeking to disrupt a two-year-old favela pacification program aimed at wresting the densely populated areas from the gangs' control.
Police said that on Thursday they will focus on the Vila Cruzeiro favela in northern Rio, where they say drug dealers have fled after they were forced out of 13 other slums.
Overnight Wednesday to Thursday six buses were torched, said police, and ten suspects were arrested on drug trafficking charges and sent to maximum security prisons in distant states.
Since Sunday 47 people have been arrested, some of them caught holding bottles filled with gasoline. Police have also confiscated weapons and drugs, and interrogated 112 suspects.
Around two million of Rio's inhabitants - a third of the population - live in more than 1,000 slums.