Strange circles Appear in the sea in front of Croatian islands

Many unusual circles have appeared around the Croatian islands, causing the residents to worry. Some even say its aliens that cause it, because they often see circle formations in the sky above the location the circle are in the water. The circles are evenly spaced apart and are found around several islands. During last year’s routine underwater mapping, 28 perfect round shapes were discovered
in the underwater vicinity of Dugi Otok Island. Each having 50 meters in lenght, the circles are 300 meters away from each other