TRENTON, N.J. (AP) — Thousands of southern New Jersey residents who lost power during severe weather might not get it back until late Friday, nearly a week after the storms hit, according to utility officials who said Sunday that the damage was more severe than what Tropical Storm Irene wreaked last summer.

Two young cousins camping with their families were killed in the storms struck the region early Saturday with heavy rain, dangerous lightning and strong winds with gusts of more than 70 mph. Atlantic and Cumberland counties were hit hardest in New Jersey by the storm, which forecasters say was caused by a rare weather phenomenon known as a derecho: a fast-moving line of severe winds associated with a squall of violent thunderstorms.

Crews worked Sunday to clear downed trees and power lines along with other debris while homeowners made repairs to damaged property Sunday as temperatures remained in the mid-90s and heat indexes hovered around 100 degrees for the second straight day. States of emergency remained in effect in Atlantic County and in several municipalities.

Scattered storms moved through the area on Sunday night, affecting mostly southern New Jersey but reaching as far north as Warren County, the National Weather Service at Mount Holly reported. Some power lines were knocked down as heavy rain fell, and portions of Cape May and Ocean counties were pelted with hail before the storms moved off into the Atlantic Ocean.

"I can't recall a storm like this, the type of damage we're dealing with," said Vince Maione, the chief operating officer of Atlantic City Electric. He said that while Irene produced more outages when it hit in August, the degree of damage was greater from this storm, adding that many repairs will require work beyond the typical steps of clearing trees or minor fixes.

Strong winds from the storms that began late Friday toppled trees onto cars and blocked roads from Indiana to New Jersey and south to Virginia. More than 3 million people lost power and 13 were killed. Unlike a hurricane that moves slowly enough for cleanup crews to get into place ahead of time, the storm's lack of warning was expected to complicate efforts to repair damage.

Atlantic City Electric continued to make good progress in its restoration efforts, thanks in part to help from crews from several utilities in northern New Jersey and New York, said spokesman Matt Likovich. But citing the devastation caused by the storms, Likovich warned that some customers may not have electrical service back until late Friday. He said priority was being given to hospitals, fire stations, water filtration plants and police stations.

At the storm's peak, about 206,000 customers lost power. That was down to about 114,000 by early Monday.

Gov. Chris Christie, who toured the area Saturday, asked residents to be patient amid the tough conditions. He also assigned the National Guard to deliver fuel for generators and water.

Residents also were being urged to stay away from all downed wires, even if they don't appear to be active, and to not disrupt utility crews.

The storm was blamed for the deaths of two boys, ages 2 and 7, in Salem County. They were camping at Parvin State Park in Pittsgrove with their families when a pine tree fell on their tent. The boys suffered serious injuries and died shortly afterward, authorities said. They were identified only as being from Millville and from Franklin Township.

Winds associated the storm also apparently sparked a fire that damaged a 104-year-old church in Longport.

Authorities believe the winds knocked a utility pole into the tower of the Church of the Redeemer early Saturday morning, sparking an intense blaze that severely damaged the building. No injuries were reported.