President Donald Trump said Wednesday that meeting Las Vegas doctors and the mass-shooting survivors they have been treating made him 'proud to be an American.'

And he 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.

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

Before coming home to Washington, the president embraced the role of consoler-in-chief, speaking to America's collective sadness through a bank of TV cameras in a prepared speech

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'

Security is still tight in Sin City, with police and Secret Service out in full force as the commander-in-chief made the rounds

Air Force One taxied to a stop with the Mandalay Bay Resort Casino in the background - the building where mass-murderer Stephen Paddock opened fire on a coutry music festival from behind a smashed window

At the end of the visit Air Force One also passed by the hotel

The President would have had an up close view, as the airport is blocks away from the hotel, with the horrible scene in between

'I said, "If you are ever in Washington, come on over to the Oval Office." And they're all saying, "We want to do it! How do we do it?"'

'And believe me, I'll be there for them.'

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.

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.'

'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

'We know that your sorrow feels endless,' Trump told the families of those who perished. 'We stand together to help you carry your pain. You're not alone. We will never leave your side'

The president embraced the role of consoler-in-chief, speaking to America's collective sadness through a bank of TV cameras.

'Many families tonight will go to bed in a world that is suddenly empty. The people they so dearly love were torn away from them forever,' he said.

'Our souls are stricken with grief for every American who lost a husband or a wife, a mother or a father, a son or a daughter.'

'We know that your sorrow feels endless,' Trump said. 'We stand together to help you carry your pain. You're not alone. We will never leave your side.'

Earlier, 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.

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

Trump praised the 'tremendous bravery' of some survivors who 'were badly wounded because they refused to leave. They wanted to help others because they saw people going down all over.'

Trump said he has invited some of the shooting victims to the White House: 'I said, "If you are ever in Washington, come on over to the Oval Office," and they're all saying, "We want to do it! How do we do it?"'

'People that would not be around today are up there,' he said, referring to the hospital's upper floors.

'And they'll be leaving the hospital in a week or two weeks or five weeks. And in some cases even in a few days. It's amazing.'

'We met quite a few people. And believe me, they are very lucky to be here.'

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.'

Trump shook hands with a Las Vegas Metropolitan Police Department officer who rushed into danger on Sunday night despite being off-duty at the time

'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

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.

Sunday's mass-shooting left at least 59 victims dead and more than 500 people in area hospitals.

Trump tweeted from aboard Air Force One that he was 'to pay my respects with @FLOTUS Melania. Everyone remains in our thoughts and prayers.'

The president was met on the tarmac by Las Vegas Mayor Carolyn Goodman, Clark County Sheriff Joseph Lombardo and Gov. Brian Sandoval.

Donald Trump arrived Wednesday at Las Vegas McCarran International Airport before meeting with shooting victims and first responders who saved lives during Sunday's gun massacre

Las Vegas Mayor Carolyn Goodman (left), Clark County Sheriff Joseph Lombardo (center) and Republican Nevada Gov. Brian Sandoval (right) greeted Trump and first lady Melania

Sheriff Joseph Lombardo, who is in charge of the investigation and has been briefing the media on a regular basis, saluted the president when he arrived

On Tuesday the president was consoling another group of Americans: Puerto Ricans whose island was leveled last month by Hurricane Maria and is still almost entirely without power.

Wednesday's trip marks his first attempt to console Americans who have lost family members to a horrendous gun massacre.

Trump spoke about Las Vegas shortly before his trip began.

'Well, it's a very sad thing. We're going to pay our respects and to see the police who have done really a fantastic job in a very short time,' he said as he left the White House.

'And yeah, they're learning a lot more. And that'll be announced at the appropriate time. It's a very, very sad day for me personally.'

Wednesday marks President Trump's first experience consoling family members of mass-shooting victims

The president tweeted from aboard his plane that he was going to 'pay my respects' along with Melania

Before he left town, the president got some familiar gripes off his chest, blasting the media he derides as 'fake news.'

'Wow, so many Fake News stories today. No matter what I do or say, they will not write or speak truth. The Fake News Media is out of control!' Trump wrote.

In an earlier tweet, he wrote: 'A great day in Puerto Rico yesterday. While some of the news coverage is Fake, most showed great warmth and friendship.'

The president described the Las Vegas situation briefly aboard Air Force One Tuesday. ''It's a very horrible thing even to think about,' Trump said. 'It's really horrible.'

Trump walks past hurricane wreckage as he participates in a walking tour with Melania in Puerto Rico. On Wednesday, he visited Las Vegas to comfort victims of a shooting rampage

Trump began his second consecutive day of visiting Americans coping with tragedy with a shot at 'Fake' news

'The Fake News Media is out of control!' he told his followers on Wednesday

Trump speaks to reporters before boarding Marine One on the South Lawn of the White House in DC on Wednesday. He then flew to Andrews Air Base and on to Las Vegas

During his Tuesday visit, in addition to promising Puerto Ricans the government would be there for them, Trump repeatedly complimented his own disaster efforts.

He gave himself an 'A +' and copiously thanked responders and local officials who have praised him.

Trump told Hannity on Fox News Tuesday night that he knows the island 'very well' having been there 'many times.'

'We have to help. We've done a fantastic job. It was. An A + in Texas. An A + in Florida,' he said.

'And we may have done our best work here but it hasn't been appreciated but actually if you see over the last couple of days, people are seeing what we've done,' Trump said.

Trump tosses paper towels into a crowd as he hands out supplies at Calvary Chapel in Guaynabo, Puerto Rico, on Tuesday. He was in Puerto Rico to survey hurricane damage

En route to Puerto Rico Tuesday morning, Trump lashed out at the Las Vegas gunman

'He's a sick man, a demented man, a lot of problems I guess and we're looking into him very, very seriously, but we're dealing with a very sick individual,' the president said.

Trump also promised reporters 'we'll be talking about gun laws as time goes by,' in the aftermath of Sunday's mass shooting in Las Vegas.

However, when asked about a particular piece of legislation, which would make it easier for gun owners to purchase silencers, he wasn't ready to delve into specifics.

'Well talk about that later,' Trump told the journalists gathered on the South Lawn of the White House.