From the gallery: https://pbase.com/britestar/insurrection_at_the_capital
Some of the "gas masks" provided to members of Congress are being worn in this image.
In addition to firearms (& zip ties to be used as restraints), the invading mob also threw unidentified cannisters of some sort of gas through the doors and broken windows as they broke into the capitol. In this image, the captive members of Congress have no idea of what was going on. I'm not sure FOX's later announcement of "Shots Fired" meant from the mob or from the defending capitol police or from both. All was chaos as more & more of the mob broke into the building in a frenzied intent of doing physical harm.
Copyrighted Image. DO NOT DOWNLOAD, copy, reproduce, or use in any way without written permission from Elizabeth Bickel.