The other victims include Zack Barth, a Houstonian who works for Austin Congressman Roger Williams; Matt Mika, a Tyson Foods lobbyist; and U.S. Capitol Police officers Crystal Griner and David Bailey.
The suspected gunman, James T. Hodkinson, died after a shootout with police, according to President Trump.
Here's a look at the frightening events as they unfolded:
6:30 a.m.: Republican congressmen, lobbyists, and staffers gathered at Eugene Simpson Stadium Park to begin practice for Thursday night's charity baseball game, a tradition in Congress.
Shortly after 7 a.m.: Two Congressmen told ABC News a man walked up and asked "whether it was Republicans or Democrats out there." It is not clear whether the man was the shooter or a bystander.
7:09 a.m.: The first reports of the shooting reached Alexandria police. Alabama Congressman Mo Brooks told CNN he realized Rep. Scalise was screaming because he had been shot.
At least 50 rounds were shot, according to witnesses.
7:12 a.m.: Capitol Police officers exchanged gunshots with the shooter at the park.
7:14 a.m.: Officers shot the suspected shooter.
Scalise and four other victims were rushed to area hospitals. Three others were also treated for injuries.
8:01 a.m.: The White House said Trump was briefed on the shooting.
Trump released a statement saying: "Our thoughts and prayers are with all affected."
8:23 a.m.: Police said the suspect was in custody and no longer a threat.
9:30 a.m.: The FBI joined the investigation.
10:39 a.m.: Austin Congressman Roger Williams confirmed Zack Barth was shot.
The Houstonians was expected to make a full recovery.
11:10 a.m.: James T. Hodgkinson identified as the suspected shooter.
11:36 a.m.: Trump said Hodgkinson died from his injuries.
6:41 p.m.: Trump leaves hospital with the First Lady after visiting Scalise.
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