Tom Williams/CQ Roll Call/AP

As Deputy Assistant Secretary of Defense Laura Cooper was sitting down to testify, the roughly couple dozen Republicans stormed through the three different doors, a source in the room said.

Rep. Bradley Byrne yelled in committee Chair Adam Schiff's face, but Schiff didn't engage. Other Democrats, including Val Demings, screamed back at both Byrne and Rep. Louie Gohmert, who were yelling about the process.

"It was closest thing I've seen around here to mass civil unrest as a member of Congress," according to a source in the room.

Cooper left the room while the Republicans refused to leave.

The source says the Capitol Police and sergeant at arms have been consulted as members refuse to leave the room.