Saturday’s early morning thunderstorm was blamed for at least three deaths in South Jersey, including a 7-year-old Millville boy who was struck by a fallen tree while camping.

Two young children, cousins from Millville and Franklin Township, Gloucester County, were killed when hurricane-force winds snapped the tree under which the families had set up their tents at Parvin State Park in Pittsgrove Township, Salem County.

A third person died presumably from drowning after a skiff capsized in Absecon Bay near Brigantine.

Two boaters were able to swim to shore and summon help from Brigantine police, who alerted the Coast Guard. The Coast Guard dispatched a rescue helicopter crew from Air Station Atlantic City about 3:20 a.m. that found the missing boater and directed a small-boat crew to the scene, but the victim was pulled unconscious and unresponsive from the water. He was later pronounced dead.

Petty Officer Nick Ameen said a language barrier hampered a rescue effort for the missing boater.

The identities of the boaters were not released Saturday.

In Parvin State Park, 10 people in two related families were camping at adjacent campsites when the storm approached, felling hundreds of mature trees. As the storm intensified about 1:30 a.m., the two families huddled under the same tent at Campsite 9.

The boys, ages 2 and 7, died when the 25-foot top of a pine tree fell on the tent.

“A very large pine tree that was stressed by these winds snapped in half. The top portion of the tree — really the top half — broke and fell onto the tent site where this family gathered,” said Larry Ragonese, spokesman for the state Department of Environmental Protection.

One other person suffered minor scratches. The state closed the park until further notice.

The state did not release the names of the children or their families. State Police are investigating the accident, Trooper Christopher Kay said.

Downed trees, power lines and flooding hampered rescue efforts by local fire companies, the State Police and the State Park Police, Ragonese said.

“There was really vicious winds and rain. It was just a brutal storm,” Ragonese said.

One of the children was pronounced dead at the park. Another was taken to the Rosenhayn Volunteer Fire Company’s firehouse, where he, too, was pronounced dead.

Firefighters at Rosenhayn declined to discuss the rescue Saturday.

“Part of the problem was just getting there. We had two-dozen personnel who responded to the scene,” Ragonese said. “But responders had difficulty because of downed wires and trees and flooding that made it difficult.”

The remaining campers were evacuated from the park and left behind their vehicles, which were trapped by downed trees.

By midday Saturday, the state had cleared roads enough to let campers reclaim their belongings and vehicles. The state helped some people make other camping arrangements at unaffected parks or campgrounds. Campers also can get a refund or credit toward a future stay, DEP spokesman Larry Hajna said.

Hajna, who visited the park Saturday, said many of the campers seemed to be in a state of disbelief.

“It sounds like conditions were so brutal that you couldn’t really move. They stayed put until the storm passed,” he said. “It was a terrible storm. Winds were probably in excess of hurricane force.”

Parvin State Park has 56 tent and trailer sites and 18 furnished cabins, all of which were booked for the pre-July 4 weekend, Ragonese said.

“We’d like to get it reopened for the holiday, but we have to look at it first,” Ragonese said.

Contact Michael Miller:

609-272-7217