NANTUCKET, Mass. — Multiple shark sightings near swimming beaches prompted the closure of the entire south shore of Nantucket on Wednesday, officials said.

Nantucket Harbor Master Sheila Lucey said there were at least five shark sightings throughout the day and all of them were less than 15 feet from the shore.

The beaches closed Wednesday afternoon included Cisco Beach, Surfside Beach, Nobadeer Beach, Miacomet Beach, and Medaket Beach.

Officials said one of the shark sightings at Cisco Beach was confirmed while the other reports from Surfside Beach and Nobadeer Beach were unconfirmed fin sightings.

Lucey said Nantucket officials are asking people to stop fishing on swimming beaches as their bait may be attracting sharks, The Boston Globe reports.

The region around Cape Cod has been drawing more great white sharks in recent summers as the animals feast on a large population of local seals.