The European Commission said on Friday it had detailed its charges against four European traders of North Sea shrimps it believed may have formed a cartel, colluding on prices and dividing up markets.

The Commission, which acts as competition regulator in the 27-member European Union, did not identify the firms involved, but said its investigation centered on markets in Belgium, France, Germany and the Netherlands, reports Reuters.

The charges, set out in a "statement of objections," stem from investigations resulting from raids on several North Sea shrimp producers in March 2009.

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