The state Department of Environmental Protection says the two boys, ages 2 and 7, were killed early Saturday at Parvin State Park in southwestern New Jersey's Salem County.
The boys were cousins, officials said.
Authorities say the boys' families had been camping at adjacent sites when the storm hit, and the families decided to huddle together in one tent. They say the heavy winds and rains from the storm snapped a pine tree, which then fell on the families' tent.
The boys suffered serious injuries and died. They were from Millville and Franklin Township.
Authorities are investigating.
Meanwhile, thousands of utility customers in southern New Jersey lost power when the storms moved through the region early Saturday, and crews were working to restore service on a day where temperatures were expected to soar into the mid-90s.
The storms, which featured heavy rain, lightning and strong winds that gusted as high as 60 mph, knocked down numerous trees and power lines throughout the region.
Atlantic City Electric says more than 96,000 customers had no service late Saturday morning. Atlantic and Cape May counties appeared to be the hardest hit areas.
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