Emergency personnel work to clean up a tractor-trailer accident Friday on the Pennsylvania Turnpike in Brickerville, Pa.. The closing of the turnpike because of this accident compounded the road closure problems throughout the central portion of Pennsylvania.

Allentown, Pa. ? The last of hundreds of stranded motorists were freed but Pennsylvania highways remained shut Friday as crews struggled to clear ice and snow following a monster storm that has been blamed for at least 24 deaths in the Northeast and Midwest.

Gov. Ed Rendell apologized for Pennsylvania’s “totally unacceptable” handling of the storm and a tie-up on a 50-mile stretch of Interstate 78, which stranded hundreds of motorists for as long as 24 hours. He blamed an “almost total breakdown in communication” among state agencies.

State Transportation Secretary Allen D. Biehler said I-78 and large portions of I-81 and I-80 would remain closed so workers could clear them. The icy mixture, up to 6 inches thick, became rock-hard as overnight temperatures plummeted to the low teens and single digits.

The sprawling storm system, which caused deaths from Nebraska to New England, blew out to sea Thursday, leaving huge snow piles, frigid temperatures and tens of thousands without power.

Numerous areas saw more than a foot of snow, and about 300,000 customers lost power at the height of the storm.

Vehicles started getting stuck on I-78 around midday Wednesday, but it took more than a day for state police to close all the entrance ramps. Pennsylvania officials, including Rendell, could not explain why it took so long.

At New York City’s Kennedy Airport, JetBlue travelers continued to experience delays and cancellations Friday as the airline struggled for a third day to recover from a storm-related backlog that left angry passengers stuck in grounded planes for hours.

The company had hoped to have things back to normal by Friday morning.

“It didn’t work as well as we planned,” spokesman Bryan Baldwin said. “It’s going to take longer than we anticipated to do that.”

Pennsylvania authorities blamed the I-78 snarl on the severity of the storm and jackknifed tractor-trailers. They said all motorists had been cleared off the highways by early Friday.

“This storm was rare because of the unusual amount of snow and ice,” Biehler said Thursday.

“This series of accidents that blocked our way made it really, really difficult.”

The I-78 jam was so bad that National Guardsmen in Humvees had to ferry food, fuel and baby supplies Thursday to stranded motorists.

Drivers were outraged, especially because it had taken state police so long to close all the entrance ramps.

“Why would they have that exit open if they were just going to let us sit there?” a crying Deborah Miller said Thursday. Her 5-year-old son was trapped in the car with her, running a 103-degree fever from strep throat.

At least 24 deaths were blamed on the storm system and accompanying cold: six in Ohio; three in Nebraska; two each in Illinois, Indiana, New York, New Jersey and Delaware; and one each in Missouri, Pennsylvania, Virginia, New Hampshire and Louisiana.