-- At least 20 Republican members of Congress were at this morning's baseball practice in Alexandria, Virginia, when a gunman began firing, injuring House Majority Whip Steve Scalise, R-La., and at least four other people.
The GOP lawmakers who make up the 34-member team were practicing for Thursday's annual charity congressional baseball game.
Zach Barth, a staffer for Rep. Roger Williams, was also injured. Barth is "receiving medical attention but is doing well and is expected to make a full recovery," according to Williams.
"He has been taken to a local hospital, and we're awaiting word on his condition. Matt has worked for Tyson Foods for more than six years, and we're deeply concerned about him and his family," a Tyson spokesperson said in a statement.
Rep. Brad Wenstrup of Ohio treated Scalise immediately after he was shot. Wenstrup has a medical degree and served in Iraq as a combat surgeon.
"I felt I was back in Iraq but without my weapon," Wenstrup told Fox News.
Here is the full list of attendees at the routine early-morning baseball practice that turned into a terrifying, chaotic scene:
Present during the shooting
Practiced but left before the shooting
Team members not present at the time of the shooting
ABC News' Cindy Smith, Benjamin Siegel, Ali Rogin, MaryAlice Parks, Jordyn Phelps, John Parkinson, Angie Yack, Arlette Saenz, Zunaira Zaki and Michael Del Moro contributed to this report.