A Rhode Island beach has been evacuated as authorities investigate reports from beachgoers of a boom in the sand that knocked a woman into a rock wall.

State Department of Environmental Management spokeswoman Rayne Maguire tells the Providence Journal the woman was taken to a hospital from Salty Brine beach in Narragansett after the incident around 11 a.m. Saturday. No other injuries have been reported.

DEM enforcement Sgt. Thomas Silvia said authorities are looking for a suspect they believe planted something in the sand then fled.

A witness told the newspaper he heard a boom and saw the woman get knocked over a few feet from him. Mario Lewis of West Greenwich says he saw no debris or smoke.

State police and local police are investigating with a bomb squad.  (Associated Press)