HAMPSTEAD, N.C. (AP) - A county official says reports of an active shooter at a school in North Carolina turned out to be a malfunctioning water heater.

News reports quote Pender County emergency management director Tom Collins as saying that noise from the water heater was taken for the sound of gunfire at Topsail High School on Friday morning. The earlier report of shots fired provoked a massive response by law enforcement and caused the school district to reroute buses and put schools on lockdown.

Capt. James Rowell of the Pender County Sheriff's Office was quoted as saying in local reports that deputies swept the school but found no evidence that any shots had been fired. He said deputies did find an HVAC unit that was malfunctioning and making sounds similar to gunshots.