The security services seized the fish from a Moroccan truck on November 6 when the driver failed to provide necessary documents for importing the fish load.
The cargo included a range of merchandise, including sole, turbot, and wedge sole.
Police investigated the driver, who will have to pay a fine of €3,001 or 50,000 for not complying with Royal Decree 418/2015 of May 29.
This is not the first time when Spanish police have seized Moroccan fish cargo. In August in Malaga, police, and customs blocked a refrigerated truck because they suspected the driver of smuggling cannabis inside the Sardines coming from Morocco.
Police lowered the temperature on the 24,000 kilograms of sardines in the truck. The change in temperatures meant that sardines became unfit for human consumption.