The gunman, James T. Hodgkinson, a 66-year-old unemployed home inspector from southern Illinois, was killed in the shootout. Two Capitol Police officers assigned to Scalise's security detail were wounded.
Hodgkinson, who had been living in his van in Alexandria for the past few months, had posted anti-Trump rhetoric on his Facebook page, and had written letters to his hometown newspaper blaming Republicans for what he considered an agenda favoring the wealthy.
The mass shooting, coming amid harsh political rancor and a divided country, reverberated through Washington and beyond, as Trump and members of Congress began talking about unity for the first time since the presidential election.
The targeted lawmakers were practicing for the Congressional Baseball Game, a charity competition against a team of Democrats. The game will be played on Thursday night at Nationals Park as planned.
Several congressmen at the Eugene Simpson Stadium Park in Alexandria praised the Capitol Police officers who engaged Hodgkinson, including two who were injured. One lawmaker said the baseball team members would have been sitting ducks had the gunman been able to make it onto the field.
Rep. Jack Bergman, R-Mich., a retired Army general, said, "If he had been able to gain entrance to the field, it would have been a whole different story," he said.
As of Wednesday evening, Scalise, La., remained in critical condition after undergoing surgery at MedStar Washington Hospital Center, a hospital spokeswoman said. A lobbyist, a congressional aide and a Capitol Police officer also were shot, while a second officer was struck by shrapnel. Rep. Roger Williams, R-Texas, injured his ankle while helping others take cover.
In a televised statement from the White House, Trump called for people to come together and commended the injured officers.
Trump said he spoke with Scalise's wife and offered his full support to the congressman's family, calling Scalise a friend, patriot and fighter. He also thanked the first responders.
"We may have our differences, but we do well in times like these to remember that everyone who serves in our nation's capital is here because, above all, they love our country," Trump said.
Lawmakers and bystanders described a horrific attack that began shortly after 7 a.m., when the shooter began firing more than 50 rounds from a military-style rifle and a handgun, taking aim through the chain-link fence.
Scalise was felled by a bullet to the hip as he fielded grounders at second base, witnesses said. Then the aide and the lobbyist were struck as the gunman moved methodically around the fence and toward the home-plate backstop. As Scalise crawled across the field, leaving a trail of blood, the gunman advanced toward a dugout, where several people were hiding.
Congressmen said the Capitol Police officers emerged from the dugout, moving toward the gunfire. A woman walking her dog heard a female officer scream, "Drop your weapon," before the gunman "shot her and she fell to the ground." House Majority Leader Kevin McCarthy, R-Calif., said the officers "went out into the fire to draw the fire. The shooter was moving toward the dugout where the members were, and they were able to take him down."
Authorities said five people were taken to hospitals, including Hodgkinson. Matt Mika, a lobbyist for Tyson Foods, was in critical condition at George Washington University Hospital, a spokeswoman said. Zach Barth, a legislative correspondent for Rep. Roger Williams, R-Texas, was shot in the leg and released from the hospital Wednesday afternoon.
The House Speaker's office identified the injured Capitol Police officers as Special Agents David Bailey, who was treated and released from a hospital, and Crystal Griner, who was struck in the ankle and hospitalized in good condition. Capitol Police Chief Matthew Verderosa said both are expected to recover fully. Police identified a third officer who participated as Special Agent Henry Cabrera. They did not say which officers fired their weapons.
Scalise's office said in a statement that the congressman was in good spirits and speaking to his wife, Jennifer, by phone before he went in for surgery. He has been in Congress since 2008 and represents a district that includes some New Orleans suburbs and bayou parishes. He and his wife have two children.
Verderosa said it "will take a while to sort through all the details" during the investigation, which is now being led by the FBI. Tim Slater of the FBI said it is "too early to tell whether anyone was targeted. ... It's really raw now."
But focus immediately turned to political statements Hodgkinson made on social media, interactions he had with lawmakers, and run-ins he had with law enforcement officials near his home in Belleville, Ill., a suburb of St. Louis.
Rep. Jeff Duncan, R-S.C., told reporters that, just before the shooting, he spoke briefly with a man he believes was Hodgkinson, and that the man "asked me if the team practicing was a Democrat or Republican team." Duncan added, "I told him they were Republicans. He said, 'OK, thanks,' and turned around.
"I'm shaken up," Duncan said. "My colleagues were targeted today."
Sen. Bernie Sanders, I-Vt., said Hodgkinson volunteered on his 2016 Democratic presidential campaign, although an aide said that he had no formal role and that no one could remember him. Sanders denounced the shooting, saying on the Senate floor that he was "sickened by this despicable act."
Police in Belleville reported responding in March to a complaint that Hodgkinson was shooting at the end of his street, firing 50 rounds "in the pine trees." Police said that he had a valid license for the weapon, and that he agreed to stop when they told him to.
Rep. Mike Bost, R-Ill., who represented the district where Hodgkinson lived, said that Hodgkinson had contacted his office 14 times via email or by telephone, and that although he never made threats, "he was always angry."
Stephen Brennwald, a lawyer who lives in Alexandria, said he realized after seeing Hodgkinson's photo on the news that he was the same man who had been hanging out for at least the past several weeks in the lobby of a YMCA adjacent to Simpson field. Brennwald said Hodgkinson would regularly show up first thing in the morning - about the same time the shooting took place - and look at his laptop or stare out the window.
"He never worked out. He never talked to anybody. He never did anything," Brennwald said.
Authorities said Hodgkinson used a rifle and a handgun in the attack. They are investigating whether they were obtained legally.
The shooting started at 7:09 a.m. at the popular park on East Monroe Avenue in the Del Ray neighborhood of Alexandria, near Old Town Alexandria and the Potomac Yard shopping complex on Route 1. The Republican lawmakers were holding their final practice before Thursday night's game, a traditional event designed to bolster goodwill between two sides of the partisan aisle.
Scalise, who plays second base, was accompanied by members of the Capitol Police Department's executive protection unit because as majority whip, he is the third highest-ranking member of the House. His security detail was positioned behind the first base dugout; witnesses said the shooter started on the other side of the diamond.
About 20 people were on the field at the time, many catching fly balls from batting practice, and when the gunfire started, players and onlookers took cover in dugouts, under a sport-utility vehicle or in the open on the ground. Barton, the team manger, said the gunman, dressed in blue jeans and a blue shirt, shot at Scalise at second base and fired toward third baseman Trent Kelly, R-Miss.
Rep. Mo Brooks, R-Ala., saw the shooter and described the scene as "bedlam." Brooks had just stepped up to home plate with a bat in his hand when heard the first two or three shots.
He heard Scalise scream, then go down.
Brooks said he ran behind the batting cage and watched Scalise drag himself toward the outfield. Brooks lay down in the dirt with two or three others, but then realized that if the shooter moved, "he'd have a clear shot." So he ran to the first-base dugout. There, he found a staff member who had been shot in the leg, and he said he used his belt as a tourniquet.
He said two officers emerged from the dugout and advanced toward the oncoming bullets.
Sen. Jeff Flake, R-Ariz., still wearing red and white baseball shirt with "Republicans" plastered on it, said he recalled seeing the rifle and then hearing shots. He said the gunman was firing "at anybody he could hit. I don't know if anybody was targeted, but I just remember seeing some of the gravel bounce up as gunfire hit."
Katie Fillus of Alexandria had just gotten out of her car to walk her dogs in the park when she said she heard "very, very loud popping sounds." She said, "Everybody started screaming, 'Hit the ground! Hit the ground!' "
Fillus said she lay flat in the field as the gunshots grew louder - "like he was walking across the field toward all of us."
She said she watched a female officer yell at the gunman and then get shot. "She fell on the ground in front of us," Fillus said. "And I belly crawled, dragging through the mud. I got to the car and I ducked under the car."
Bullet holes were left in windows of the YMCA, and bullets were in the swimming pool. Several churches in Alexandria planned community prayer services for Wednesday evening.
Rep. Mike Doyle, D-Pa., and Barton - managers of the respective teams, said they will still take to the field Thursday night.
"We're united not as Republicans and Democrats but as United States representatives," Barton said. "It will be 'play ball' tomorrow night, 7:05."
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)
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