Hundreds of thousands of people took to the streets of the Brazilian city of Rio de Janeiro for the start of the annual carnival parades.
Over two nights, tens of thousands of people will gather in the Sambadrome to watch as 12 Samba schools stage a spectacular parade which is shown live on national television.
The Uniao da Ilha samba group opened the night, introduced by a fireworks display and a 500-strong drum line.
It is the first time the carnival has been held since Rio was chosen to host the Olympic Games in 2016 and correspondents say the organisers are keen to show they can safely stage major events.
However, the parades have already proved controversial.
One samba school chose seven-year-old Julia Lira as its queen and had to fight off a legal challenge to have her banned. She briefly burst into tears during the parade.
The role of carnival queen is usually occupied by models and TV stars. The use of sexual imagery provoked the protest that seven-year-old Julia's role was inappropriate.
The carnival is divided between elaborate parades in the Sambadrome and the carnival street parties.
City officials are keen to promote a safe image of Rio. So far there have been few reported incidents of crimes.
While many costumes are minimal, others are more modest. Temperatures were sometimes higher than the Sahara Desert!
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