Police in the Brazilian city of Rio de Janeiro have launched a major operation to try to stop a wave of violence by criminal gangs

For days, suspected gang members have been blocking roads, burning cars and shooting at police stations. Military police have been deployed in 17 different slum districts. Rio's governor says the violence is retaliation by drugs gangs who have been driven out of some areas by a police pacification program. More than 1,000 officers have been taken away from desk jobs to join the surge on the streets, the military police said, and 300 extra motorcycle police are on patrol. Rio de Janeiro's state governor Sergio Cabral has also asked the central government for police reinforcements from outside Rio to keep the main highways open. At least one suspected gang member has been shot dead. More than eight others have been arrested, including four suspects who were found with petrol bombs in the Copacabana beach neighborhood. Armed men have been blocking some of the main roads leading out of Rio, robbing motorists and setting their vehicles on fire. The authorities are convinced that the attacks are being orchestrated by drugs gangs in retaliation for being forced out of their traditional strongholds in some slum districts by police pacification units.