The collision Sunday killed three of five teen-agers who were walking along the railroad tracks in Falls Township, Bucks County, about 25 miles northeast of downtown Philadelphia. The other two teens, who were not struck, escaped without injury.
"It's tragic for the engineer, because in cases like this you can often see it but not prevent it," Amtrak spokeswoman Karen Dunn said.
The names of the three victims, ages 14, 15 and 19, were expected to be released Monday after autopsies were conducted. The two younger victims lived in nearby Morrisville, while the identify of the older victim was still being confirmed Sunday, said acting Falls Township Police Chief Neil Harkins.
"Their backs were to the train," said Harkins. "We don't know if they heard the train or not."
The two teens who were not hit were a boy and a girl. They only knew the 19-year-old by his first name, making identification difficult.
The southbound Acela Express train was traveling from Boston to Washington, D.C. The train can hit top speeds of 150 mph, but currently does so only on small stretches of the route in Massachusetts and Rhode Island.
The accident happened Sunday afternoon in a remote section behind an industrial building.
None of the approximately 300 passengers on the train were hurt, Dunn said. They were delayed at the scene for about two hours until the train could continue to Philadelphia. Passengers then had to get on other trains so the train involved in the accident could be examined as part of an investigation, she said.
Service on other Amtrak trains in the corridor was restored within 30 minutes, Dunn said.
Marty Burke, a member of the Fairless Hills Fire Company, said working at the scene was devastating.
"It's really a tragedy kids and at Christmas. This is going to ruin a lot of families," Burke said.
According to Dunn, there is a fence around the tracks to make this sort of accident less likely. "We're not sure what the circumstances were yet. I haven't gotten a report from the engineer," she said.
She said that engineers need at least a mile to stop a fast-moving train if they see someone on the tracks.
Acela Express links Boston and New York in about three hours, 30 minutes, compared with about four hours for regular trains. The service, which has been phased in over the last year, connects Washington and New York in about two hours, 44 minutes, compared with about three hours for its predecessor, the Metroliner.
In September, a 71-year-old Warwick, R.I., man was also killed by an Acela Express train while walking on railroad tracks near his home.
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