CHARLESTOWN, R.I. (WPRI) — The Department of Environmental Management said a juvenile thresher shark was spotted off the coast of East Beach in Charlestown on Saturday afternoon.

Mike Healey, a spokesperson for the DEM, said the beach was evacuated from about 3:30-4:30 p.m. when a lifeguard noticed a fin about 10-15 feet off the shore. The fin then showed up again about 30-40 yards from the beach.

After viewing a video of the fin, officials were able to determine it was a thresher shark, about 6-feet long. They believe it came close to the shore to feed on baitfish.

The thresher shark is one of the most common found in R.I.’s coastal waters. It is named for its long, scythe-like tail, which is used to stun fish before preying on them.

Healey added that their fin-sighting protocol is for swimmers to evacuate the water after an actual or suspected shark sighting. Beach staff, marine biologists and environmental police then look into the sighting to see if it was an actual shark.

Last month, a fin-sighting caused the evacuation of the water at beaches in Narragansett, however, it turned out to be ocean sunfish.