WESTERLY, R.I. (AP) — Rhode Island beachgoers are puzzled and concerned about a mysterious object lodged about 10 feet underwater just off Westerly’s East Beach.

The circular object has stainless steel legs and is capped with concrete. It appears to be either very heavy or rooted in place.

The Westerly Sun reported Friday the object was first seen last summer but could not be found on follow-up attempts.

East Beach Association President Peter Brockmann says he’s been asking experts about the object’s origin. He says the best tip he received was from University of Rhode Island oceanographers, who said it could be a stand for a U.S. Army Corps of Engineers device used to monitor currents and sediment flow during dredging projects.

Brockmann says they will try to uproot the object soon.