Rio de Janeiro Carnival 2018 Photos: Brazilians dance away troubles at Carnival

Amid a lacklustre economy, a massive corruption investigation and increasing political polarisation, Brazilians are letting off steam at Carnival, a holiday long considered a safety valve for social and political tensions.

Known for elaborate - or skimpy - costumes and intense samba competitions, Carnival celebrations also frequently take on serious subjects. This year, for instance, women's groups are highlighting the sexual harassment and unwelcome touching that many face during the celebrations and throughout the year on Brazil's streets. Others have called attention to housing shortages or are criticising politicians who have been accused of corruption.

But many see Carnival as a time to take a break from those weighty issues.

"Carnival transcends politics - it's (a celebration) of the Brazilian people," said Hector Batelli, a 30-year-old lawyer, who on Saturday was enjoying a Sao Paulo Carnival street party, known as a bloco. "So we put aside politics to have a party, to celebrate."

Brazil has recently emerged from one of the worst recessions in its modern history, and the largest corruption investigation in Latin America has resulted in the prosecution and jailing of many of its business and political leaders, decimating its political class and undermining faith in its institutions.

That has led to deep political polarisation and even the rise of radicalism ahead of this year's elections. Presidential preference polls give a lead to former President Luiz Inacio Lula da Silva, who has been convicted on corruption charges, but about whom Brazilians are split: About half want to see him in power again, while half want to see him in jail. In second place is far-right congressman Jair Bolsonaro, who glorifies the country's 1964-1985 dictatorship and has been ordered to pay fines for offensive comments.

The deep divide was reflected in plans for duelling blocos this year. A group called Right Sao Paulo planned a party named after a notorious organ of repression of the country's former military regime, known as the Department of Political and Social Order, or DOPS. Others responded by planning parties that would denounce the regime.

In the end, a judge ruled that the Bloco "Basement of the DOPS 2018" could not appear in public.