A Dutch national is said to be at the heart of a large tax fraud involving mussels, currently being investigated by the Dutch and Belgian authorities.

Belgian media say hundreds of thousands of euros are involved and the central figure in the case is a major Dutch shellfish trader.

The fraud, involving value-added tax (btw), was uncovered when the man’s book-keeping came under scrutiny and did not add up.

The investigation has been ongoing for a year, the Belgian papers said.