Carnival celebrations in Brazil reached their height Monday with the massive, extravagant parades of Rio de Janeiro's samba schools.

Six of the schools, with from 3,000 to 5,000 members each, danced and sang through the night from Sunday evening to the next morning when they poured into the Sambadrome.

Each samba school picks a theme for its parade and plays its signature song for close to 85 minutes.

The schools that got the best reception from the 72,500 people packing the stands of the Sambadrome were Mangueira, Salgueiro and Beija-Flor, the last three to make their appearance in the early hours Monday.

Beija-Flor surprised the Sambadrome crowd with several technological innovations, notably a giant screen on which members of the audience could post photos using a cellphone app.

Parades in the Sambadrome will resume Monday night, when dancing along the "samba runway" will be the Mocidade, União da Ilha, Vila Isabel, Imperatriz, Portela and Unidos da Tijuca schools, all organized in the poor "favelas" (shantytowns) of Rio.

The best school will be chosen by a jury that will announce its decision on Wednesday.

Aside from the Sambadrome, the frenzied partying will continue Monday through the streets of Rio de Janeiro, where parades are programmed for 75 musical groups known as "blocos," which play free of charge and ask only that members of the public join in and have some fun.

The Carnival parades and bands are leaving a tremendous trail of litter this year because some of the street cleaners in Rio have been on strike since last Saturday demanding better pay. EFE