Thousands of revellers have filled the streets of Rio de Janeiro for the city's famous carnival celebrations, amidst tight security following days of street violence between security forces and drug gangs.
One day into the festival and hundreds of thousands of revellers thronged the streets, dancing and drinking.
Army tanks and trucks have been patrolling the streets for the first time in the carnival's history, with soldiers watching the parade ground in the centre of the city where the carnival takes place.
Rio state governor Rosinha Matheus said 36,000 police officers and 3,000 soldiers would keep the peace under an operation dubbed "Safe Rio".
So far no incidents have been reported, and many Rio residents expressed the hope that the carnival would pass of peacefully.
"Things calmed down when the army got here, I wish they'd
never leave," taxi driver Jose Carlos Marques Rito told the Associated Press news agency.
"But the violence was bad for the carnival. People are afraid."
Red Command blamed
The tight security follows several days of violence which left several dead.
More than 50 buses have been torched
Drugs gangs burned and machine-gunned buses, attacked police posts and set off small bombs in a beachfront area where hotels are packed with tourists.
One armed gang of about 30 men initiated a three-hour shoot-out with police on one of Rio's biggest thoroughfares, Brazilian media reported.
The authorities are blaming the violence on a drugs cartel, the Red Command, which has thousands of heavily armed followers and controls many of Rio's shanty towns.
And, coming during the traditional festival - which is celebrated with fancy-dress parades, music and dancing - it is a blow to the city's reputation.
Officials expressed concern that the violence would affect the city's tourist industry, with more than 400,000 tourists expected to visit the city for the parade.
However Major Gilberto Tenreiro of Rio's tourist police said he thought the worst was over.
"The violence was a phase that has already passed," he told news agency Associated Press.
"We are doing everything to make sure tourists can enjoy carnival without any worries."