A seal and three spinner-dolphins were found washed up on Greek islands' shores in the last few days, the 'Archipelagos' Institute of Marine Conservation reported on Thursday, tortured and mutilated.

The seal, found in the northern Dodecanese islands, was discovered with its hind flipper tied in a rope, while the three dolphins, located at three different areas in the northern Aegean, were found with flippers removed, most likely by a knife, says the institute; it added that these were evidently cut off purposely to drown the dolphins.

According to the institute, although this species of dolphin has not previously approached fishing vessels, in recent years spinner-dolphins have been swimming near trawlers more often, as the continued overfishing has depleted food sources. Judging by their injuries, "it is clear that the dolphins were pulled alive on the deck of fishing boats and were thrown back into the sea still alive but with their fins cut off so that they couldn't swim, eventually suffering a torturous death", emphasized the Director of the institute Thodoris Tsibidis.

As Archipelagos officials added, "It is not possible to ascertain whether this murder was perpetrated by a Greek or a Turkish fishing vessel, as trawlers from both countries are active in this sea region."

Konstantinos Aravossis, Secretary General for Natural Environment & Water of the Ministry of Environment and Energy, has reportedly asked Archipelagos institute to coordinate actions with ministerial and other authorities to investigate and fully document the situation.

This latest report comes only weeks after the Archipelagos institute reported the recent killing of seven Mediterranean seals (Monachus-Monachus) found dead at Greek shores.