Trooper Matthew Burrows of the state police barracks in Milton said the bus was extensively damaged when it hit the rear end of a flatbed trailer that was hauling garbage at about 1:30 a.m. in the westbound lanes of I-80 in Union County's White Deer Township.
Greyhound spokeswoman Alexandra Pedrini said 38 of the 49 passengers transported to five hospitals were treated and released by late Wednesday afternoon, and then placed on replacement buses to their final destination. She said the bus driver, Sabrina Anderson, 42, was one of the four people in critical condition.
The bus was heading from New York City to Cleveland. Anderson has been with the company for more than 12 years, Pedrini said.
The driver of the tractor-trailer, Akos Gubica, 36, of New Jersey, told The (Sunbury) Daily Item that his rig was struck from behind by the bus. Pedrini declined to comment on that, saying the company was cooperating with authorities in their investigation and was conducting an internal probe.
The section of I-80 where the crash occurred was shut down for about 15 hours.