LEHIGHTON, Pa. (AP) — A New Jersey man died and at least two other people were treated for injuries after an apparent lightning strike at an eastern Pennsylvania lake, authorities said.

Officials said the man was swimming at Beltzville State Park in Carbon County shortly after 7 p.m. Saturday when the strike occurred. Terry Brady, spokesman for the Pennsylvania Department of Conservation and Natural Resources, said a preliminary investigation indicates that he managed to get out of the water but became unresponsive in the beach area.

The Lehigh County coroner’s office said 38-year-old Jose Lopez-Hernandez, 38, of Camden, New Jersey, died just after 3 a.m. Sunday at Lehigh Valley-Cedar Crest. An autopsy is scheduled Monday to determine the exact cause of death.

Park manager Devin Buzard said two or three other people were treated after the lightning strike. Staff began warning visitors to seek shelter and leave the water ahead of the storm, as per protocol at the park, where there were about 3,000 visitors during peak hours of the day, he said.

There were about 20 cloud to ground strikes in southern Carbon County during the period of the strike, according to Valerie Meola, a meteorologist at the National Weather Service in Mount Holly, New Jersey. That compares to more than 600 instances of cloud to ground lightning in an area of New York, where several people were struck and one died, she said.

In Bethlehem, attendees at the annual Musikfest music festival were told to leave the festival stages when the storm rolled in and music was stopped for about an hour and a half. Meola said such caution was warranted, but the storm in that area wasn’t particularly notable for cloud to ground strikes, with most of the action taking place in the sky as lightning jumped from cloud to cloud.

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