BALTIMORE (WJZ) — Questions persist about a congressional motorcade that investigators say led to a deadly crash on a busy Maryland interstate Wednesday morning.

U.S. Capitol Police will not release the names of the powerful senators who were traveling to a retreat, causing a dump truck to slam into one of the drivers who stopped for the senator’s motorcade on Interstate 70.

Now there are concerns about whether the motorcade itself was needed, and whether it created a dangerous situation.

New video shows Democratic senators leaving the Capitol on two buses during Wednesday morning rush hour. The VIP motorcade was surrounded by a U.S. Capitol Police detail.

The motorcade stopped traffic as they went from D.C. through Maryland, on their way to a luxury retreat in Shepherdstown, West Virginia.

While pulled over for the motorcade on I-70 in Frederick, Patricia Nazzal captured the moment tragedy struck.

“I was like, ‘Oh, it’s got to be either the president or something like that. Whoever – somebody important – so let me start videotaping,'” said Nazzal. “All of a sudden, I hear ‘bam.’ They come sliding across in front of us, and you can see how close they were to that motorcade. It just looked like out of a movie. It was heartbreaking.”

Maryland State Police say a dump truck failed to stop, causing a chain reaction accident that killed someone pulled over for that motorcade and injured two other drivers.

Nazzal shared extended video exclusively with WJZ that shows the fiery wreck just inches from the congressional bus.

“That scared me,” said Nazzal. “When they said it could explode, and then you hear this popping, and they’re trying to move the bus back, too.”

“[Reporter: You’re the only one that actually has that video?] I wanted you guys to be able to see it specifically because you can see more in that video,” said Nazzal.

WJZ investigator Mike Hellgren has been asking tough questions about all aspects of this motorcade, but so far, authorities are not revealing much.

We wanted to know: was it necessary to have a motorcade and stop traffic for a trip to a retreat? How many members of congress were being escorted and who were they?

U.S. Capitol Police were in charge, and tell us they ‘…do not discuss our protectees or the means and methods by which we protect them.”

Both of Maryland’s senators, Ben Cardin and Chris Van Hollen, tell WJZ they drove their personal vehicles separately to the retreat at the Bavarian Inn, which bills itself as a four-diamond getaway on the Potomac.

WJZ has also learned high profile Senator Bernie Sanders and Minority Leader Chuck Schumer attended, but we don’t know if they were on those buses, or just how many lawmakers may have come inches from danger.

We also don’t know who felt it was necessary to give them this kind of escort.

“Honestly, when I saw that big of a deal, I just assumed that it had to have been the president,” said Nazzal. “They looked like important people.”

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