RIO DE JANEIRO, Brazil -- A World Cup stadium being built in the isolated Brazilian state of Amazonas may not become a white elephant after all.

At least one judge in the area has come up with a post-World Cup use: a prisoner processing centre.

Brazil is readying 12 stadiums for next year's World Cup, and several -- including the new stadium in Manaus -- will be little used after the tournament.

FIFA and Brazilian officials were the subject of widespread protests three months ago during the Confederations Cup, a warm-up for the World Cup.

Millions took to the streets to protest spending billions on sports events in a country with poor public services, high taxes and stark social inequality.

Brazil is spending an estimated $3.5 billion on stadiums for the World Cup, part of a total of $13.3 billion for related infrastructure needed to host football's biggest event.

Spending on the 2016 Rio de Janeiro Olympics will be similar.

Alvaro Corado, spokesman for the Amazonas state court system, told The Associated Press Tuesday that Judge Sabino Marques had proposed a novel idea.

"He would, perhaps, suggest to the government of the state of Amazonas that the stadium be used as a processing centre for prisoners after the World Cup," Corado said, quoting Marques.

Marques is also the president of a group that monitors the prison system in the state.

The new 44,000-seat stadium in Manaus, being built at a cost of $275 million, will host only four World Cup matches. The city of 2.3 million has no team in Brazil's first or second division, and little football tradition.

The potential for building white elephants is similar for three other new stadiums: in the capital Brasilia, in Cuiaba in the southwest, and in Natal in the northeast.

FIFA requires only eight stadiums for the World Cup, but Brazil decided to have 12 -- under pressure from politicians who used the construction projects to provide jobs and political loyalty.

Brazilian Sports Minister Aldo Rebelo has defended the legacy of the stadiums as "centres for sports and non-sports events" and has suggested they would be places for conventions, shows and fairs.

Other Brazilians officials have said cities will need to be creative to find uses for the stadiums.