Twenty-eight female guards were unfairly dismissed by a security company because the client‚ Metrora.
The samba school Unidos da Tijuca won the official competition Wednesday in Rio de Janeiro’s world-famous carnival.
With a performance late Monday at the Marques de Sapucai Sambadrome, Unidos da Tijuca beat rival groups Salgueiro and Vila Isabel by a narrow margin.
The winning performance, featuring seven huge floats and 3,600 dancers in costumes, honoured Brazilian singer-songwriter Luiz Gonzaga, who died in 1989 but would have turned 100 this year.
Supporters of the champion samba school celebrated their success, with plenty of dancing and beer.
Parades late Sunday and Monday at the Sambadrome are the highlight of the Rio carnival, and are attended by more than 70,000 spectators every night.
Thirteen samba schools competed for the prestigious carnival title, graded in 10 fields including choreography, music and floats by a 40-member jury.
Meanwhile, in Sao Paulo, the group Mocidade Alegre was declared the winner.
On Tuesday, violence involving scores of people led to a suspension of the announcement about the champion, amid complaints from the other samba schools that the competition was rigged for Mocidade Alegre.
Shortly before the winner was announced Tuesday, a member of the Imperio da Casa Verde samba school stormed the jury box and tore up their completed scoring papers before fleeing, all captured by television cameras.
The suspect was later identified and arrested along with four other samba school members.
After the incident, members and supporters from several samba schools poured into the Anhembi Sambadrome and vandalized facilities.
A float from the Perola Negra group was set ablaze at the sambadrome, with the owners blaming rivals from the Gavioes da Fiel group.
On Wednesday, Sao Paulo Mayor Gilberto Kassab threatened to take away financial assistance from city authorities for samba schools unless those responsible for the melee are punished.