Sen. Bernie Sanders was forced to take cover behind a car Thursday afternoon as a high-speed chase came to an end near him on the grounds of the U.S. Capitol.

Sanders was unharmed in the incident, but the driver of the vehicle that was evading police is dead, according to multiple press reports.

Spokesman Michael Briggs says the Vermont independent was returning to the Dirksen Senate Office Building from a caucus meeting in the Capitol when the incident took place. He was standing at the corner of 1st and Constitution Ave. NE with Sen. Roger Wicker (R-Miss.) and about to cross Constitution Ave.

"He saw police cars racing by and heard four or five shots," Briggs says. "A police officer nearby told him and other senators to get on the ground."

After taking cover behind a car for "a couple minutes," Briggs says, Sanders was ushered back inside by the Capitol Police. 

Briggs says the senator was not particularly rattled by the incident, though he added, "Tensions are pretty high around here with the shutdown and the shooting a couple weeks ago at the Navy Yard."

"He'd rather be talking about the decline of the middle class," Briggs said.

Vermont's other two congressional delegates, Sen. Patrick Leahy and Congressman Peter Welch, were inside at the time of the shooting, their aides said.

"Sen. Leahy was attending a meeting in the Capitol when the incident occurred," a Leahy spokesman said in a written statement. "His security detail informed him of the incident, and he immediately sheltered in place and instructed his offices to shelter in place."

According to Welch spokesman Ryan Nickel, "The Congressman was on the floor of the House about to speak about the government shutdown. House proceedings were interrupted by Capitol police and staff.  Members and staff on the House floor, including Congressman Welch, were ordered to shelter in place in the House chamber."

Below, watch a clip from MSNBC's interview with Sanders about the incident.

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