A man who was shot in the leg during the Las Vegas mass shooting didn't let his injury hold him back from standing up to greet President Donald Trump and First Lady Melania Trump.

Thomas Gunderson was attending the Route 91 Harvest Festival on Sunday night when he was horrifically injured when Stephen Paddock, 64, sprayed bullets on more than 20,000 concertgoers.

Gunderson, of California, said he was running toward Mandalay Bay when a bullet pierced his leg.

Thomas Gunderson (pictured, left and right), who was shot in the leg during the Las Vegas mass shooting, didn't let his injury hold him back from standing up to greet President Trump and First Lady Melania Trump (right)

'Hi Thomas. How are you?' Melania Trump asks as she tells him not to get up. 'I'm okay,' Gunderson is heard saying as he gets to his feet and the pair shake hands

President Trump and First Lady Melania flew to Las Vegas where they visited several victims of the shooting on Wednesday.

But they were suprised when Gunderson stood up to greet both of them despite his leg injury, and a family member captured the entire moment on video.

Gunderson is seen trying to sit up in the hospital bed as the first lady walked in.

'Hi Thomas. How are you?' Melania Trump asks as she tells him not to get up.

'I'm okay,' Gunderson is heard saying as he gets to his feet and the pair shake hands.

They then prepared for the president to walk through the hospital room door as the video showed Trump greeting doctors, nurses and staff.

They then prepared for the president to walk through the hospital room door as the video showed Trump greeting doctors, nurses and staff (left). 'Hey, this guy looks tough to me,' the president said as he shook Gunderson's hand (right)

Gunderson held onto Trump's hand as he thanked him for his visit. Trump then gave Gunderson a pat on the back and asked: 'How's it going?'

Gunderson (left and right) posted the video to his Facebook page with the caption: 'I will never lie down when the President of this great country comes to shake my hand!'

'Hey, this guy looks tough to me,' the president said as he shook Gunderson's hand.

Gunderson held onto Trump's hand as he thanked him for his visit.

Trump then gave Gunderson a pat on the back and asked: 'How's it going?'

Gunderson posted the video to his Facebook page with the caption: 'I will never lie down when the President of this great country comes to shake my hand!

'There may be plenty of issues in this country but I will always respect my country, my president and my flag. Shot in the leg or not, I will stand to show my President the respect he deserves!' Gunderson wrote.

On Gunderson's patient board in his hospital room, he also had the hashtag '#MAGA' written under the statement: 'What's important to me.'

MAGA is the acronym for Make America Great Again, Trump's presidential campaign slogan.

On Gunderson's patient board in his hospital room, he also had the hashtag '#MAGA' (pictured) written under the statement: 'What's important to me.' MAGA is the acronym for Make America Great Again, Trump's presidential campaign slogan

Trump, standing with first lady Melania Trump, spoke to reporters on Wednesday after visiting doctors and shooting survivors at University Medical Center in Vegas

Trump and surgeon Dr. John Fildes briefed the press, and the president said the hospital's medical staff 'have done a job that's indescribable'

After leaving Las Vegas Trump tweeted a video of him meeting with several victims of the horrific shooting at the University Medical Center of Southern Nevada.

'We love you Las Vegas,' he wrote in the caption of the video with the song God Bless the USA by Lee Greenwood playing in the background.

The video showed Trump and the first lady talking with patients and their families.

Earlier on Wednesday Trump said that meeting Las Vegas doctors and the mass-shooting survivors have made him 'proud to be an American'.

He also revealed that he invited many of them to visit him at the White House.

'I just met some of the most amazing people,' he told reporters at University Medical Center. 'We met patients that were absolutely terribly wounded.'

'I invited a lot of them over to the White House,' he added.

Trump praised medical professionals who have kept the death toll from growing.

'The doctors, the nurses - all of the people at the hospital have done a job that's indescribable,' he said.

'In the depths of horror, we will always find hope in the men and women who risk their lives for ours,' the president said, surrounded by first responders

U.S. President Donald Trump speaks at the Las Vegas Metropolitan Police Department with first responders who reacted to the mass shooting over the weekend

Donald Trump met with police officers and emergency crews who were called to the scene of the mass shooting over the weekend

First lady Melania Trump looks on as Clark County Sheriff Joe Lombardo is embraced by President Donald Trump after the president gave a speech in a room full of police officers and family members at Las Vegas Metropolitan Police Department headquarters

'I've always known you guys are good but you really proved it,' the president told a group of first responders singled out for their heroism

Air Force One was seen departing Las Vegas with the Mandalay Bay Resort Casino in the background - the building where mass-murderer Paddock opened fire on a coutry music festival from behind a smashed window

Trump and First Lady Melania Trump returned to the White House from Las Vegas on Wednesday evening

The hospital that the president visited saw 100 shooting-related patients on Sunday night and admitted 50 of them.

The president also met with police and first responders at the Las Vegas Metropolitan Police Department's command center.

'I've always known you guys are good, but you really proved it,' he told a group singled out for their heroism - including one officer who attended Sunday night's country music festival during his off-duty hours and sprang into action to save lives.

The president said he has always been 'a big fan' of law enforcement.

'And I guess if you can be more of a fan, I'm even more of a fan now.'

In a short speech before returning to Washington, the president said 'America is truly a nation in mourning' following the mass-murder-suicide that killed nearly five dozen.

Gunderson was one of the more than 400 victims who were injured in the shooting when Paddock opened fire from the 32nd floor of the Mandalay Bay hotel. Paddock (pictured), killed 58 people in the shooting, which is now the deadliest in US history

He praised police and first responders who ran toward the danger even as civilians were fleeing.

'In the depths of horror, we will always find hope in the men and women who risk their lives for ours,' he said.

And intoning the name of one officer who was killed in the line of duty, he said: 'The example of those whose final act was to sacrifice themselves for those they loved should inspire all of us to show more love every day for the people who grace our lives.'

Gunderson was one of the more than 400 victims who were injured in Sunday night's shooting when Paddock opened fire from the 32nd floor of the Mandalay Bay hotel.

Paddock, killed 58 people in the shooting, which is now the deadliest in US history.

Trump also said 64-year-old Stephen Paddock, who opened fire on the event from a hotel room window, is 'a sick, demented man.'

'The wires are screwed up. There might be something there,' he said.

Moments later, addressing a larger group of police at the department's operation center, the post-shooting investigation's nerve center, the president said 'it could have been worse' if officers didn't stop Paddock so soon.

Trump landed in Las Vegas on Wednesday afternoon, on his second consecutive day of visiting Americans coping with tragedy.

Elisabeth Apcar and Dashenka Giraldo, from Las Vegas, light candles for the victims of the Mandalay Bay massacre in Las Vegas on Wednesday night

A young girl inspects a makeshift memorial for the victims at the northern end of the Las Vegas strip on Wednesday night

People run from the Route 91 Harvest country music festival after gunfire was heard. Witnesses said they initially ducked down at the command of police, but panic then took hold and there was a stampede

First responders and bystanders carry an injured person to an emergency station located at the intersection of Las Vegas Boulevard and Tropicana Ave - one block north of the shooting