People walk in front of a branch of currency exchange in Sao Paulo, Brazil, on Sept. 2, 2015. (Xinhua/Rahel Patrasso)

RIO DE JANEIRO, Dec. 8 (Xinhua) -- Brazil's antitrust body has slapped five banks with fines worth a combined 183.5 million reais (54 million U.S. dollars) for creating a cartel to manipulate exchange rates, official sources announced Thursday.

CADE, an office in charge of preventing economic abuse, announced that it had hit Barclays, Citicorp, Deutsche Bank, HSBC and JPMorgan Chase with the fines for participating in anti-competitive activities.

The ruling is linked to an investigation begun in Switzerland, Britain and the United States in which 15 companies have been accused of manipulating exchange rates. The fines so far handed down in this case have reached almost 6 billion U.S. dollars.

CADE investigated the banks both for fixing rates and preventing certain exchange operators from carrying out operations. The banks are also suspected of collaborating to restrict competition in the buying and the selling of foreign currencies and to manipulate reference exchange rates.

"Anti-competitive practices have potential direct and indirect effects on Brazilian territory and potentially allowed the participating operators of positioning themselves advantageously in order to obtain profits and minimize losses, to the detriment of clients," said CADE in a statement.

CADE also opened an investigation on Wednesday into another potential cartel of banks that sought to manipulate the real's onshore exchange rate.

The investigation includes 19 executives and former executives from 10 banks, including Banco BBM, BNP Paribas, BTG Pactual, Citibank, HSBC, ABN AMRO Real, Fibra, Itau BBA, Santander and Societe Generale.