The Onondaga County Sheriff's Department on Sunday identified 18-year-old Deanna Armstrong of Voorhees, N.J., as one of the four Megabus passengers who died when the top of the vehicle hit the bridge in Salina while en route to the Syracuse bus station early Saturday morning.
Also killed was 19-year-old Kevin Coffey, a Temple University sophomore from Kansas.
A Malaysian preacher and an information technology specialist from India also died.
The driver, John Tomaszewski, 59, of Yardville, N.J., and four of the 24 other passengers were injured. One remains in critical condition and two are in serious condition.
The Megabus was carrying 29 people, including the driver, when it rammed the bridge around 2:30 a.m. Saturday on the Onondaga Lake Parkway in Salina, a suburb of Syracuse in central New York.
Twenty passengers, including seven Canadian residents, were treated and released, said Don Carmichael, a senior vice president at Coach USA, which operates Megabus.
The bus was too tall and wasn't able to clear the low-hanging span, according to Onondaga County Sheriff Kevin Walsh, who said he believed the driver made a wrong turn when getting off the interstate.
"Whether he saw the bridge, we don't know," Walsh said. "There were all kinds of warning signs at several locations, including flashing yellow lights."
It struck the bridge between two large signs warning that the clearance was 10 feet, 9 inches, photographs from WSYR-TV showed. The top level of the bus was obliterated in the front.
Police said there was no indication the driver had been drinking or using drugs.
Normally, the bus enters Syracuse on Interstate 81 and heads straight for a depot for a 30 minute rest stop, Carmichael said, but on this night, the driver left his usual route and was on a lakeside parkway that might have been unfamiliar.
"We don't know why," he said. Asked if the driver might have been lost, Carmichael said, "He had driven the route before."
The parkway and the transportation depot share the same exit off the interstate, and a driver who chose the wrong fork at the bottom of the ramp would find himself on the parkway. From there, it is only a short distance to the bridge, and in between there are no places for a driver to turn or pull off the road.
The driver had head injuries but was speaking to investigators, Onondaga County sheriff's deputy Herb Wiggins told The Post-Standard newspaper of Syracuse.
The bus left Philadelphia at 10 p.m. Friday and was headed for Toronto with stops in Syracuse and Buffalo, said Carmichael.
Passenger Lee Veeraraghavan, 27, a University of Pennsylvania student who was traveling home to Toronto, said she heard people calling for help and moaning after the crash. She told The Post-Standard she was sitting in the back of the bus on the lower level.
"I just tried to get my bearings," Veeraraghavan said. "I just remember coming to in pain and a lot of broken glass under the bus, and there was a woman's legs on top of me."
After about 15 minutes someone on the bus pried open what she thought was a door and the passengers escaped, Veeraraghavan said.
Megabus has operated the double-decker buses since 2007.