Police have arrested three Vlissingen fish traders suspected of selling undersized fish following late night raids on five trawlers in the city’s harbour.

‘We were looking for black market fish, or fish that is undersized and landed without registration,’ a police spokesman told local broadcaster Omroep Zeeland. 

Non-registered fish are not counted against quotas.

Some 150 police officers participated in the raids which were prompted by a tip off about fish being sold outside the usual channel of the fish auction.

‘It’s illegal but most of all it is disturbing the ecological balance. If you catch these young fish it means they won’t be able to reproduce,’ the police spokesman said.

All crew members were stopped and searched during the action. They are not regarded as suspects but will be questioned as the police continue to investigate their catch.