Ryan Gaskin of NY was riding the train with his two children on their way to a beach vacation.
Investigators said that it is routine for an onboard system to search for potential "abnormalities" on the freight trains about every 25 miles and send notifications to dispatch if any issues are discovered.
Amtrak reported none of the train's passengers or crew were injured, according to local news media. Some Wednesday morning trains are canceled. He said there were "few definitive facts at this early stage".
Service was disrupted due to temporary track closure for an investigation north of Washington, D.C.
The company said it is working with D.C. Metropolitan Police Department and others to review the incident.
The area where the employees were struck has two tracks that belong to CSX and two that belong to Amtrak, Weener said.
Persons struck by train 1200 blk NY Ave NE.
The train damaged by debris in Williamsburg has been terminated, said Amtrak spokeswoman Kimberly Woods. Amtrak later said on Twitter that service is expected to be restored by mid-morning.
Amtrak is not running between Washington and Philadelphia, after two railroad workers were hit and killed by a train approaching the station in Washington. Customers can expect residual delays.
Amtrak later said it is "particularly saddened that incident involved fellow railroaders employed by CSX".
The MARC Penn Line between Union Station and Carollton also was suspended Wednesday.