US Capitol Police arrested an 18-year-old man on Tuesday after he ran towards the west side of the Capitol Building carrying a loaded shotgun. The man parked a Mercedes SUV near the Capitol, then ran several hundred yards before officers stopped him and ordered him to lie on the ground. Capital Police Chief Michael Sullivan said the gunman wore a tactical vest and gloves. Officers found a Kevlar helmet and a gas mask in his vehicle. He also had additional shotgun rounds with him. The motive is still being investigated, including if members of Congress were targeted. The Capitol was not in session at the time. Chief Sullivan shared that the police have video footage of the arrest but asked the public to share any videos they may have. “Who knows what would have happened if we wouldn’t have officers standing here?” he said. Sullivan added that the department recently practiced active shooter drills in nearly the same location.