According to the Rio de Janeiro auditing court, part of the reason for this was overbilling by the contractors to the tune of 211 million reais (about $90 million at 2014 rates).

The accusations were first aired late Sunday by Globo television and the documents were seen by AFP on Monday.

One example of overbilling was cement bought at three times the market price. Another was the new roof, which cost five times as much as a similar roof on the Soccer City stadiums built in Johannesburg for the 2010 World Cup, Globo reported.

Some services, such as hiring of cranes, were simply billed twice.

Rio prosecutors on Friday demanded that contractors Odebrecht and Andrade Gutierrez -- two huge companies involved in a major corruption scandal at state oil company Petrobras -- and Delta Engenharia repay some 200 million reais.

Odebrecht told AFP that the company "reaffirms its commitment to collaborate with the authorities."