SAYREVILLE, N.J. (AP) _ A bus taking 23 people from New York to Atlantic City on a Christmas Eve gambling junket skidded off a snowy highway and flipped over Thursday, killing eight passengers.

The privately operated bus plunged about 20 feet down a slushy embankment along the Garden State Parkway, landing on its side.

Fifteen people, including the driver, were injured. Their conditions ranged from stable to critical.

Rescuers had to cut seats apart to get at some of the victims.

``We tried to get to the people who were screaming the loudest,'' said Joseph McKevitt, a member of a first aid squad. ``It didn't look a bus anymore. Seats were folded. Bodies were strewn every which way.''

Police said the weather may be a factor.

About 2 inches of snow had fallen earlier, and snowplows had cleared two of three lanes, State Police Sgt. Al Della Fave said. It was not clear which lane the bus had been traveling in.

A witness saw the bus swerve before it left the outer lanes and overturn several times down the embankment, police said.

The National Transportation Safety Board sent a team of investigators because of the large number of deaths and because the agency is in the middle of a study on the crashworthiness of buses.

``The information we gain here will be very important for that study,'' agency spokesman Ted Lopatkiewicz.

Several helicopters landed on the closed roadway to take some of the injured to hospitals. Others were taken by ambulance.

The accident shut down the southbound express lanes of the Garden State for 6 1/2 hours on one of the busiest travel days of the year. The parkway is one of New Jersey's major north-south roadways.

The driver, Valerie ``Val'' Viner, 52, was hospitalized in stable condition. He was being interviewed by police.

``I'm shocked,'' said Eddie Ginzburg, part owner of Bruins Transportation of Brooklyn, which owned the bus. ``It never happened to us before. We're a small company. My heart is just broken, you know.''

About 1,000 buses a day pour into Atlantic City, bringing gamblers to the city's 12 casinos. Many leave from New York City, and the Garden State Parkway is the quickest route.

Bruins Transportation has an average safety record, said Maureen McCarthy, a spokeswoman for the New York state Transportation Department.

The department inspected all 13 of Bruins' buses between January and September and found problems with two, which were repaired, reinspected and put back in service, she said.