RIO DE JANEIRO, Brazil -- In a mix of millennium carnival and religious mysticism, millions of revelers dressed in white packed Rio's beaches in what Brazilians called the biggest New Year's party in the world.

The beat of samba drums blended Friday night with the somber pulse of African tom-toms or "atabaques" as worshippers threw white flowers and perfume into the waves as gifts for Yemanja, the Yoruba goddess of the sea celebrated by devotees of Afro-Brazilian religions every Dec. 31.

Antonio Jorge Oliveira, 36, stood in the waves cradling his 6-month-old daughter, Ona, and gently pushed cotton into her ears to dampen the boom of the fireworks overhead.

"I took her here to thank God and to let her receive the good energies of the beginning of the millennium," he said.

Police estimated that an all-time record 5 million people crowded Rio's coastline to welcome the new millennium. About half jammed the 2.5-mile crescent of Copacabana.

The entire neighborhood was closed to cars at 6 p.m., when samba bands paraded through the streets. The roads were to reopen at 10 a.m. Saturday.

At midnight, a stunning 18-minute fireworks show erupted on Copacabana beach, highlighted by the traditional cascade of "liquid fire" from both ends of the beach. President Fernando Henrique Cardoso watched from the Copacabana Fort.

Gal Costa, Jorge BenJor, Beth Carvalho and other Brazilian pop music stars performed on stages set up on the sand.

The local phone company Telemar reported that service was slow on the beach because of so many calls by cell-phone users. But worries about Y2K problems seemed unfounded; there were no reports of disruptions.

On the recommendation of Brazil's aviation agency, airlines put no flights in the air between 11:45 p.m. and 12:15 a.m.

"The apocalypse wasn't on time, but that's Brazil for you," joked Ana Lucia Duarte, a 20-year-old researcher in Rio.

In Sao Paulo, South America's largest city, some 1 million people packed Paulista Avenue in the heart of the financial district to celebrate.

The party kicks off a year of commemorations for the 500th annivesary of Brazil's discovery by Portuguese explorers on April 22, 1500.