Updated

A St. Louis-bound Greyhound bus that overturned on the Pennsylvania Turnpike, sending 14 people to the hospital, was the first bus accident on the East Coast this year involving a commercial carrier.

The latest accident, at 6 a.m. Saturday, happened after the bus from New York City had stopped in Philadelphia and had traveled about 75 miles westbound on the turnpike on the way to a stop in Columbus, Ohio.

Trooper Glenn Fields of the state police barracks in Bowmansville said Sunday the bus was traveling in the left lane and struck a concrete barrier, then veered right up the embankment before tipping on its side. He declined to comment on other matters, such as how fast the vehicle was going.

Both state police and Greyhound officials are continuing to investigate the accident.

Unlike most of the other bus crashes along the East Coast this year, this one involved a commercial carrier, rather than a chartered tour bus or a smaller operator.

More than 30 people have been killed and more than 300 injured in tour bus accidents this year, according to Advocates for Highway and Auto Safety. That is more than in all of the last year, when 30 were killed and 272 injured in 28 crashes.

The worst accident so far this year happened March 12 when a bus returning to New York City's Chinatown after an overnight trip to a Connecticut casino flipped onto its side and struck a pole. Fifteen people were killed.

Fields and Greyhound spokeswoman Maureen Richmond said the exact number of people on the Greyhound bus on Saturday remained unclear.

Richmond had earlier said 29 people were on the bus but said Sunday she could only confirm the presence of the driver and 18 passengers, 14 who were treated at various hospitals and released and four uninjured people who resumed their trip on another vehicle. A turnpike spokesman had said Saturday that the total might be 25 because of possible duplicates on the driver's manifest.

Richmond said the driver, 24-year-old Kareem Edward Farmer of Philadelphia, had been with the company for about five months. She said she did know what speed he had been traveling but there was no indication that he had been involved in accidents before and no indication that drugs or alcohol was involved.

Farmer's father, Derrick Bivins, said Saturday that he had a brief telephone conversation with his son after the accident and that Farmer had suffered a head laceration and a cut on his arm. "He's Ok, with some stitches," Bivins said.

Richmond said the company was cooperating with an investigation by state police and was also doing its own internal investigation, which would involve "going over the bus with a fine-tooth comb" as well as interviewing the driver and talking with the passengers.