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 LGBTQ 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 LGBTQ people and "removing rights that we have already obtained." Read more via NBC