PARIS, France: After the environmental group Sea Shepherd released video and photos of a massive swarm of dead fish released by a large trawler in the French Atlantic Ocean, the European Union and France have begun an investigation.

The images showed a blanket of dead blue whiting fish floating on the surface of the Bay of Biscay, off the coast of southwest France, which the group estimates to have 100,000 dead fish.

In response, French Maritime Minister Annick Girardin tweeted that she ordered the National Center for Fishing Surveillance to investigate.

Virginijus Sinkeviius, European commissioner for the environment, oceans and fisheries, also announced an inquiry into the “national authorities of the fishing area and presumed flag state of the vessel, to get exhaustive information and evidence about the case.”

In a statement, the Pelagic Freezer-Trawler Association, which represents the Lithuania-registered trawler Margiris, which caught the fish, said that the fish were “involuntarily released into the sea” because of a tear in the trawler’s net.

It said the trawler has adapted its practices to deal with “the exceptional size of the fish currently in the area,” adding “such an accident is a rare occurrence, and in this case was caused by the unexpectedly large size of the fish caught.”

However, Sea Shepherd, which is calling for more policing of the seas, expressed its doubt that the incident was an accident and instead indicated it could be an intentional dumping of unwanted fish.