The Rio de Janeiro Carnival 2012 kicked off with more than two million people turning up for five days of non-stop partying.

The carnival has been celebrating its 93rd year with elaborate parades, dazzling costumes and samba-driven parties throughout the city.

Organisers say that nearly 2.5 million people took part in the street parades - a 20 percent increase over 2011- including around 850,000 tourists.

There were also lavish costumed parades in the city's Sambadrome arena, where samba groups tried to outdo each other with spectacular costumes and floats in front of 70,000 spectators.

Officials said they were better prepared to keep the chaos under control this year, with more portable toilets, traffic guards and paramedics, as well as a new central command centre. Only 15 people were arrested for minor offences, said police.

Some 171 street parties were scheduled across the "Marvellous City" over the weekend out of a five-day total of 400.

Rio Carnival 2012: Brazilian Beauties on Parade [SLIDESHOW]

Rio Carnival: Craziest Costumes of 2012 [SLIDESHOW]