Some 400,000 people took part in one of Latin America's biggest gay pride parades in the Brazilian city of Sao Paulo.

The annual gay pride march was headed by the city's mayor, the left-wing sexologist, Marta Suplicy who said she was proud to be the mayor of a city that serves as a showcase for gay rights in an address at the start of the march.

Organisers said about twice as many took part in this year parade then the last and attributed the huge turnout to the presence of heterosexuals who sympathise with the gay rights movement, reports news website ananova.com.

"Heterosexual couples are here with their children because they don't want them to grow up with prejudice," said Beto de Jesus, president of the Association for GLBT Pride.

He added: "They (heterosexuals) are important opinion makers that help demystify and shatter stereotypes."