Congressman Steve Scalise to undergo surgery for internal injuries as concern grows over bitter partisan politics.

Congressman Steve Scalise is in critical condition after he and three others were shot in Virginia in an attack that has intensified concerns about the sharp divide and bitter rhetoric in US politics.

A gunman opened fire on a group of Republican politicians and colleagues at a baseball field in Alexandria, Virginia, early on Wednesday as they practised for a charity baseball game. He was wounded at the scene and later died.

Scalise, the number three Republican in the House of Representatives and a strong supporter of gun rights, was shot in the left hip, suffering broken bones, injuries to internal organs and severe bleeding.

He needed several blood transfusions and will require more operations, MedStar Washington Hospital Center said late on Wednesday.

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“Rep Steve Scalise, one of the truly great people, is in very tough shape – but he is a real fighter. Pray for Steve!” President Donald Trump said on Twitter after visiting the hospital.

The assailant, identified by police as 66-year-old James Hodgkinson from Belleville, Illinois, had posted angry messages about Trump and other Republicans on social media.

Rage against Republicans

Two politicians who were at the scene of the shooting, Representatives Ron DeSantis and Jeff Duncan, indicated there might have been a political motive in the attack.

Duncan said that as he left the field, the man who would later open fire approached him in the parking lot.

“He asked me who was practising this morning, Republicans or Democrats, and I said: ‘That’s the Republicans practising,'” Duncan told reporters. DeSantis gave a similar account.

The Federal Bureau of Investigation (FBI) said it was too early to determine whether it was a deliberate political attack.

“We continue to actively investigate the shooter’s motives, acquaintances and whereabouts that led to today’s incidents,” special agent Tim Slater told reporters, adding that the FBI had recovered and was attempting to trace two weapons, a rifle and a handgun.

No one else was in custody, he said.

Hodgkinson had raged against Trump on social media and was a member of anti-Republican groups on Facebook including “The Road to Hell Is Paved With Republicans”, “Terminate The Republican Party”, and “Donald Trump is not my President”.

Investigators believe he had been living out of a van in northern Virginia since March.

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Hodgkinson frequently wrote letters to his local newspaper, the Belleville News-Democrat, complaining about income inequality, AP news agency reported.

“I know he wasn’t happy with the way things were going, the election results and stuff,” his brother, Michael Hodgkinson, told The New York Times.

Hodgkinson also had arrests in his background for a series of minor offences and a more serious battery charge.

‘Got to stop’

The shooting has provoked a wave of emotion on Capitol Hill, with Trump calling for unity, and politicians expressing concern over a possible increase in verbal or physical violence after a vitriol-filled 2016 election.

In contrast to his inflammatory reactions to some previous acts of violence, Trump avoided any mention of the political debate around the shooting during a brief address to the nation shortly after the incident.

“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,” he said.

“We can all agree that we are blessed to be Americans, that our children deserve to grow up in a nation of safety and peace and that we are strongest when we are unified and when we work together for the common good.”

‘Pray for Steve!’ Trump said after visiting Scalise at the MedStar Washington Hospital Center in Washington [The Associated Press]

Several prominent Republicans, including the president’s eldest son, were quick to link the gunfire to anti-Trump rhetoric from the left.

Donald Trump Jr retweeted a message connecting the shooting to a recent production of Julius Caesar, which featured the assassination of a ruler who resembles his father, while Newt Gingrich, the former house speaker, denounced what he said was “the increasing intensity of hostility on the left”.

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Virginia’s Democratic governor, Terry McAuliffe, urged gun control measures, while Representative Tim Ryan told reporters that Washington politicians needed to cool their rhetoric.

“We’ve got to get back to … where things aren’t so personal and we’re so judgmental of each other. It’s got to stop. A member of the US Congress got shot because they didn’t like [his] political views,” Ryan said.

Despite the shooting, the annual congressional baseball game will go ahead on Thursday as planned at Nationals Park.