— -- A routine early-morning baseball practice among Republican members of Congress today quickly turned into a terrifying scene as gunshots rang out at the field in Alexandria, Virginia.
Five people, including House Majority Whip Steve Scalise of Louisiana, were injured in the shooting. The lawmakers were practicing in Alexandria's Del Ray neighborhood for Thursday night's annual charity congressional baseball game.
Sen. Rand Paul, R-Ky., told ABC News in a telephone interview that he was in the batting cage when he heard gunshots.
"The first shot was kind of an isolated shot, and everybody kind of looks up and says, 'Hey, what's that?'"
Then "a burst of gunfire" erupted, Paul said.
"At that point, people were dropping," he said. "Scalise was shot around second base, and he crawled a little bit into the outfield," Paul added.
He said Capitol Hill police officers in Scalise's security detail exchanged gunfire with the shooter.
"These guys were real heroes, and I think without, them everybody probably would have been killed," Paul added. "Steve Scalise is in leadership, and that's the only reason there was security detail there at all. I'm sad that he was shot, but he actually saved everybody's life by being there."
In an earlier telephone interview with MSNBC, Paul said, "It would have been a massacre" if Capitol Hill police had not been present.
Rep. Brad Wenstrup, R-Ohio, told ABC News that he and Sen. Jeff Flake, R-Ariz., were among those who tended to Scalise's gunshot wound before medics arrived on the scene. Wenstrup, an Iraq War veteran and a medical doctor, said they ran to Scalise on the field and "did what I did in Iraq."
"You assess their wounds, and you cut down their clothes and look for the wound and make sure that you stop the bleeding," Wenstrup said. "He was losing a lot of blood.
"I can tell you, firsthand, Steve Scalise was extremely brave and did what he was supposed to do to minimize any damage. He had to lay in position to minimize his damage."
Wenstrup said there were about 25 members of Congress and some 40 of their staffers at the baseball field at the time of the shooting. He recalled people taking cover behind trees and then running to safer places in between rounds of gunfire.
"It's just kind of surreal when you hear that first gunshot because you can't believe it is actually happening," he said. "I think people amazingly were brave and responded appropriately."
In a telephone interview with CNN, Rep. Mo Brooks, R-Ala., recalled the moment he heard the first gunshot.
"I was on deck about to hit batting practice on the third base side, and I hear 'bam,'" Brooks told CNN. "And I look around and behind third base, in the third base dugout, which is a cinderblock, I see a rifle, and I see a little bit of a body."
Brooks told CNN the shooter appeared to be a white male, possibly middle-aged.
"I hear Steve Scalise over near second base scream. He was shot," Brooks told CNN.
He said he believes the gunman was using a semiautomatic rifle and estimated that 50 to 100 shots were fired.
Brooks said he took off his belt so he and other congressmen could use it as a makeshift tourniquet on Scalise. A source told ABC News that Scalise's injury was not life-threatening.
According to a statement from Scalise's office, he was shot in the hip, is in stable condition and is undergoing surgery.
"This morning, at a practice for the Congressional Baseball Game, Whip Scalise was shot in the hip. He was transported to MedStar Washington Hospital Center, where he is currently undergoing surgery. He is in stable condition," his office said in the statement. "Prior to entering surgery, the whip was in good spirits and spoke to his wife by phone. He is grateful for the brave actions of U.S. Capitol Police, first responders and colleagues."
Rep. Roger Williams, R-Texas, confirmed that Zack Barth, a legislative correspondent in his office, was also shot. Barth is receiving medical treatment and is expected to make a full recovery, Williams said.
House Speaker Paul Ryan later revealed that Capitol Police officers David Bailey and Crystal Griner were wounded in the shooting.
"I spoke with Special Agent Bailey and Special Agent Griner this morning. One was being treated, and one was about to go into surgery," Ryan said this afternoon while addressing the House of Representatives. "An attack on one of us is an attack on all of us."
Rep. Joe Barton, R-Texas, who is the manager of the Republican congressional baseball team, said the Alexandria Police Department and Capitol Police officers captured the suspect after disabling him.
A law enforcement source told ABC News that the suspect was injured and was transported to George Washington University Hospital. Authorities later confirmed at a news conference that the suspect was taken into custody.
In on-camera remarks later this morning, President Trump said the suspect died from his injuries.
Multiple law enforcement sources have identified the suspected shooter as James T. Hodgkinson, 66, of Belleville, Illinois.
ABC News spoke with his wife, who said he had been living in Alexandria for the past two months.
She said he had been expected to return to Illinois in the coming days.
Police said the suspect's motives remain unknown, with no nexus to terrorism so far. Police described the scene as "stable," though a "robust police presence" remains on site and the investigation is ongoing.
Authorities confirmed that Capitol Police officers were on scene when the shooting happened and exchanged gunfire with the shooter. Minutes later, officers with the Alexandria Police Department arrived. Victims were transported to local hospitals, police said.
The FBI has taken control of the large crime scene, which is about 7 miles from the White House.
The Bureau of Alcohol, Tobacco, Firearms and Explosives has two dozen personnel on the scene to conduct traces on two firearms, one rifle and one handgun.
ABC News has learned that at least 21 Republican members of Congress were at the baseball field this morning.
Another witness, Ben Childers, told "Good Morning America" that he was in his apartment when he heard gunshots. He said he saw lawmakers running off the baseball field shortly after 7 a.m. ET.
"There were three members that were kind of headed over towards our apartment, so we ran down and got them into our apartment so they could shelter in place," he said. "They also said that Steve Scalise had been shot and was on the ground on the baseball field."
ABC News' Jack Date, Jonathan Karl, Katie Kindelan, Mike Levine, Nicole Pelletiere, David Reiter, Veronica Stracqualursi and Pierre Thomas contributed to this report.