(AP) Hundreds of thousands of revelers gathered in Sao Paulo on Sunday for one of the world's largest gay pride parades with this year's event focusing on the threat of religious fundamentalism to Brazil's LGBT community.

Under a giant rainbow-colored flag, revelers of all ages, many wearing bright wigs, turned the city's Paulista avenue into a multicolored sea of people filling more than 10 city blocks. 

Organizers said they expected 3 million people to participate in Sao Paulo's 21st annual gay pride parade, though military police did not release a crowd estimate.

Grammy award-winning singer Daniela Mercury and Brazilian pop star Anitta performed at a parade that organizers said would focus on secularism and the idea that no religion is law regardless of people's individual beliefs.

Parade organizer Claudia Regina said on the event's official Facebook page that "our main enemies today are religious fundamentalists," warning that some groups insist on condemning LGBT people and "removing rights that we have already obtained."

Adopting the political tone, some revelers held up signs depicting U.S. President Donald Trump and Russian President Vladimir Putin as drag queens.

Many at the parade shared the feeling that religious fundamentalists are threatening rights.

"They just need to let us have the right to live, to have the right to be happy," said Sheila Star, a drag queen in her mid-50s.

The city of Sao Paulo said in a statement that it had invested over $400,000 in infrastructure for the parade. Tourists from all over Brazil and Latin America fly to Sao Paulo to attend the celebration.

"We see that religious parents have a lot of prejudice in accepting their own kids," said Andrea Carvalho who coordinates the Mother's for Diversity group and flew from Santa Catarina to Sao Paulo for the parade.