Lifeguards posted shark warning signs at Waimanalo Beach Park this afternoon after a lifeguard spotted a shark in the area.

EMS spokesman Bryan Cheplic said that a beachgoer told a lifeguard that a shark was in the area at about 2:30 p.m. The lifeguard investigated, saw the shark and the signs were posted. Swimmers were warned not to go into the water at Waimanalo.

It was not known what type of shark it was or how large it was.

Cheplic said there were numerous other shark sightings reported around Oahu, but the Waimanalo sighting was the only one that was confirmed.

The situation will be reassessed tomorrow morning, Cheplic said.