The U.S. Senate was in summer recess and the majority of lawmakers were not in their offices.

"If you are inside the Senate Buildings, everyone inside should be sheltering in place as the report was for a possible active shooter. It should be noted that we do not have any confirmed reports of gunshots," the U.S. Capitol Police said in a post on social media.

Police said they were responded to an emergency call.

https://www.marketscreener.com/news/latest/Active-shooter-reported-at-US-Capitol-police-say--44498594/