Aug. 22 (UPI) -- Federal authorities are taking command of an investigation into the collision between two commuter trains in Philadelphia Tuesday morning, which left dozens of riders injured.
An incoming train struck a parked and unoccupied train at a terminal in Upper Darby, Pa., injuring at least 42 people, officials said.
The Norristown High Speed Line train arrived at the 69th Street Transportation Center, a busy terminal in the Philadelphia area's SEPTA commuter system, shortly after midnight and plowed into the empty train that was essentially parked there, WCAU-TV reported.
Most of the injured were sent to eight area hospitals, and at least four are listed in critical condition. None of the injuries appeared to be life-threatening, SEPTA said.
The train's conductor was among those injured, Upper Darby Mayor Thomas Micozzie said. Penn Presbyterian Hospital released the conductor after treating him.
The National Transportation Safety Board took over the investigation of the crash, said Eric Weiss, a spokesman for the agency.
A passenger, identified only as Ronnie, told WCAU-TV, "I stood up to get off, to get ready to get to my bus on time -- and smack, it hit the other trolley, parked. My face hit the wall, put a big hole in the wall and I went straight down and I blacked out.
"There was blood everywhere. The driver is all banged up and there was this one girl bleeding out of her face pretty bad."
Ronnie said at two stops prior to the crash, the Norristown train traveled through the stations and stopped -- and reversed to pick up passengers.
SEPTA spokeswoman Heather Redfern said the crash is under investigation.