The incident was reported at Orchard Beach just before 5:30 p.m.
Beachgoers abandoned their belongings and ran for their lives when a vicious storm cell blasted through -- seemingly out of nowhere.
Officials say a total of six people were struck by lightning while sitting on the sand, including a 13-year-old boy who is in critical condition.
All of the victims were taken to Jacobi Medical Center. The other victims are said to be stable.
"It was bad everybody was running, lightning falling everywhere, lighting struck like 30 feet from me," beachgoer Ralph Gonzalez said. "One lightning came down and next thing you know the cloud came above us and lightning just started falling everywhere all around us."
The ages and genders of the other victims are not yet known.
"You can't, there's no rationalizing it, it's just Mother Nature if you wanna call it that," Gonzalez said. "At this point, it's like you know, lives are lost, so it's just sad, all around sad day."
An official with the NYC Parks Department released the following statement:
"Prior to the incident, lifeguards had cleared all swimmers from the water, and Parks staff made announcements over the public address system instructing patrons to clear the beach. Our hearts go out to the victims of this tragic incident."
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