NTSB: Cause Of Ellicott City Derailment Unclear

Investigators with the National Transportation Safety Board say they're still not sure what caused the derailment of a train in Ellicott City, Md., overnight that claimed the lives of two 19-year-old women.

The three staff onboard the train told investigators that they saw nothing and felt nothing prior to the derailment around midnight. Emergency brakes on the train were deployed automatically, not manually, when 21 cars of the 80-car train went off the rails.

The train was carrying coal, and that was what caused the deaths of Elizabeth Nass and Rose Mayr. They were sitting on the edge of a bridge that spans Main Street in Ellicott City, Md., when coal spilled out of derailing cars and buried them. One of the teens had posted a photo from the bridge on Twitter minutes before the accident. It's too early to determine whether the presence of the two women had any role in the derailment, investigators say.

"We're looking at every single aspect of this occurrence. Rail, track, witness statements, event recorders, video equipment ... all of this is going to be looked at in-depth," says Jim Southworth, lead investigator for the NTSB.

The three-member crew on board the train told investigators they "saw nothing" and "felt nothing" prior to the derailment, Southworth adds. Once the first car started going off the rails, it would have automatically triggered the train's braking system.

"It was an automatic function of the air brake system," Southworth says.

Residents living nearby the train crossing could hear and feel the accident when it happened.

"I was getting a glass of water and the train goes by a couple times a day, but this time it was so loud," said Lauren Ward, who lives just a block from the accident. "It was straight screeching — it sounded like the brakes were on. And the table that I was near was kind of shaking; it was unreal."

Both victims were from Ellicott City and graduated from Mount Hebron High School; Nass was a student at James Madison University, while Meyer attended the University of Delaware. The teens were sending tweets earlier in the evening saying they were drinking on the bridge.

The train was traveling from Grafton, W.V., to Baltimore, according to CSX spokesman Bob Sullivan.