Two fish processing factories have been raided by police as part of an investigation into illegal landings. The Fresh Catch plant in Peterhead and the Shetland Catch in Lerwick were raided by police and the Scottish Fisheries Protection Agency (SFPA).
Warrants were executed at both sites and the SFPA and the Crown Office are now conducting criminal investigations into "alleged offences".
The SFPA is responsible for the enforcement of fisheries regulations.
A statement issued by the Scottish Executive said: "The agency takes fishing-related crimes seriously and is committed to acting on evidence to protect Scotland's fish stocks.
"It would not be appropriate for the executive or the Crown Office to make any further comment at this stage."