National officials leading the probe into why a CSX train derailed early Tuesday morning in Ellicott City, resulting in the death of two teens, said they are investigating what caused the incident.

“I can't speculate on that right now; it's day one," said Jim Southworth, spokesman for the National Transportation Safety Board (NTSB), during a press conference in downtown Ellicott City Tuesday.

When Patch asked whether the two teens' presence on the tracks caused the derailment, Southworth said: "I don’t know anything about that at this time. It’s another area that we’ll look into quite closely."

Elizabeth Conway Nass and Rose Mayr, both 19, of Ellicott City, died in the Tuesday 12:02 a.m. incident in which the train passed behind them on the Main Street bridge, cars tipped over and buried them in coal, according to police. 

They were both one week away from returning to college. 

They were facing east toward Baltimore County with their backs to the train as it passed a few feet behind them, police said.

Investigators learned from preliminary investigation that an emergency brake automatically activated on the train, Southworth said.

Automatic activation of the emergency brake generally shows that there was a break in the airline on the train somewhere, said Southworth.

The three-member crew—an engineer, conductor and training engineer—on board the train said during interviews with NTSB investigators that they “felt nothing, they saw nothing,” said Southworth during the press conference.

NTSB is leading the investigation and will be cleaning up the crash site in downtown Ellicott City with partners from CSX, Howard County and the Federal Railroad Administration, said Southworth.

The on-site work would likely last through at least Wednesday, stated Southworth.

Teams are relocating the 59 train cars of the 80-car train that did not derail, said Southworth. Trucks were taking coal off the site below the Main Street bridge as well.

"These cars [were] full cars; a lot of them dumped ther loads," said Southworth.

The trains were carrying coal from West Virginia to Baltimore, according to a statement from CSX.

"We had to move the coal to get into some of the areas to look into the parking lot," said Southworth.

Six cars fell off the bridge into the county-owned parking lot below the railroad bridge, according to Howard County Executive Ken Ulman.

In addition to many other factors, the nine-member NTSB group is evaluating witness statements and footage from the train, said Southworth.

Videos from the locomotive were taken from the train and are being transferred to a laboratory in Washington, D.C., where he said they would be evaluated.

Southworth repeatedly stated that it was the first day of investigation.

“I want to emphasize this is day one of the fact-gathering. These accidents happen very quickly, a matter of seconds sometimes,” said Southworth. “Investigations are quite lengthy. That’s on purpose….[NTSB is] investigating this accident to determine not just what happened but to determine why it happened...no stone unturned.”

NTSB, which works to improve public safety through research, is usually on the scene for a few days to one week, though the actual investigation lasts approximately one year, said NTSB spokesman Eric Weiss. His team includes rail experts, signal experts, track experts "and if we need to, we can call in the metallurgists," said Weiss.

The NTSB does not investigate every crash, except it is statutorily mandated to investigate all plane crashes.

"We selectively investigate accidents in other modes such as marine, rail and highway," said Weiss, "that are significant enough that we feel we could learn from them."

Related articles:

• Train Derailment Victims Had One Week Before Returning to College

• Police: Teens Who Died in Trail Derailment Were Buried Under Coal

• Train Jumps Tracks in Howard County

• Ellicott City Train Derailment Victims Tweeted From Tracks Before Death

• 'We Mourn With You': Howard County, Region Reacts to Train Derailment

• PHOTOS: Train Derailment in Ellicott City

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