The European Union is looking into reports that cheap seafood is often mislabeled as choice fish in some of the Belgian capital's fine restaurants and even in EU cafeterias.

The Oceana environmental group said Tuesday it found that 30 percent of seafood it tested in and around EU institutions in Brussels was a different fish than was labeled on the menu. In the cafeterias of the EU, which sets the fisheries policies for the 28-nation bloc, the total amount of falsely labeled fish stood at 38 percent.

EU spokesman Alexander Winterstein said "we take this very seriously."

Oceana said 95 percent of what was labeled Bluefin tuna — a fatty, sublime sushi favorite — was actually a less expensive species. In 13 percent of the cases, cod was also mislabeled.