The sharks were spotted at Hempstead Beach around 11:30 a.m., Friday, Aug. 19.
According to Town of Hempstead Supervisor Don Clavin, the town has been using drones, and lifeguards on jet skis to scan for sharks after an unusual number of sightings due to warmer waters.
The sharks were spotted by lifeguard Lauren Marquaret in knee-deep water chasing bait fish.
Clavin says the sharks, some identified as bull sharks, are drawn to the warmer waters of Long Island.
"The bull sharks are aggressive," Clavin said.
Swimming was reopened at 1:30 p.m. but would depend on any additional shark sightings.
The town has developed a policy including purchasing jet skis and drones, and extra training for lifeguards to spot fins, in an effort to protect residents.
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