The Guardian is reporting that divers found numerous dead sharks in Colombia’s Malpelo marine sanctuary and witnessed 10 fishing boats flying Costa Rican flags in the area.

According to The Guardian, Colombian officials estimated as many as 2,000 sharks including hammerhead, silky, and Galapagos sharks may have been have harvested by the fishing boats. The estimate of sharks killed was reportedly reached by the assumption that each boat could harvest 200 sharks. It was not reported how many shark carcasses were found by the divers, although a diver provided video footage of multiple finless sharks.

The Costa Rican foreign ministry “energetically condemns” the reported actions and said it would prosecute if Costa Rican ships were involved. Three of the ships witnessed by the divers were reported by name. According to The Guardian report, the vessels identified were the Marco Antonio, the Jefferson and the Papante.