President Donald Trump doubled down on an earlier tweet when speaking with reporters Tuesday morning, saying he will prosecute protesters who try to tear down statues after police stopped a group from toppling a statue of President Andrew Jackson outside the White House Monday night.

As he departed for Phoenix from the White House South Lawn, Trump thanked police for stopping protesters — whom he called “vandals, hoodlums, anarchists and agitators” from succeeding.

“Last night we stopped an attack on a great monument monument of Andrew Jackson and Lafayette Park,” Trump said, adding that “numerous people” are already in jail and more are going “today.”

Trump has called himself a “fan” of Jackson.

“We are looking at long term jail sentences for these vandals, hoodlums, anarchists and agitators. Some people don’t like that language, but that’s what they are: Bad people. They don’t love our country, and they’re not taking down our monuments,” Trump continued. “I just want that to be clear.”

He said if states can’t handle protesters, the federal government will, and to expect an executive order to discipline those tearing down statues “shortly.”

“I will have an executive order very shortly. And all it’s really going to do is reinforce what’s already there, but in a more uniform way,” Trump said. “If the state governments, as you see them, all over, Seattle. They’re very weak. And in Minnesota, they might need help. If they need help, the federal government is willing to help them.”

“If these hoodlums come around, and if the states can’t handle it, we are ready, willing and able to help as we did in Minnesota,” he added, referring to when the National Guard was sent in after George Floyd’s death.

Earlier Tuesday, Trump tweeted he “authorized” the federal government to “arrest anyone who vandalizes or destroys any monument, statue or other such Federal property in the U.S.”

Trump also wrote the offense would be punishable with up to 10 years in prison.

“This action is taken effective immediately, but may also be used retroactively for destruction or vandalism already caused. There will be no exceptions!” he wrote on Twitter earlier Tuesday morning.

On Monday night, protesters filled Black Lives Matter Plaza in Washington, just outside the White House, and some spray-painted the letter “BHAZ” — short for “Black House Autonomous Zone” on the columns of St. John’s Church. Tents were also set up outside the church where Trump took his infamous photo op with a bible less than a month ago.

Trump has repeatedly railed against the autonomous zone in Seattle — saying he could clear out protesters there in minutes.

His comments come as protesters against police brutality and systemic racism have called for statues and other monuments of historical figures with ties to racism or slavery to be taken down.

Police eventually intervened and used chemical irritants, again, to disperse the crowd in Lafayette Park Monday evening, but protesters still had managed to climb atop the statue and tie ropes around Jackson and his horse in an attempt to bring it down from its base, which was spray-painted with the word “killer.”

Trump cited the Veterans Memorial Preservation or “such other laws that may be pertinent” to enforce the arrests.

One section of the act states that a person who willfully injures or destroys veteran memorials — or attempts to do so — shall be fined and/or imprisoned no more than 10 years.

It’s not the first time Trump has expressed disdain at Seattle’s autonomous zone, a version of which he can now find outside his front door.

At his Saturday rally in Tulsa, Oklahoma, he said it would take him “less than an hour” to clear the zone if Democratic Gov. Jay Inlsee of Washington state called him. Trump said he would “love to do it.”

“Now these are anarchists, these are not protestors,” Trump said, speaking of Seattle. “Could you imagine if people just even slightly to the right tried to take over Seattle? They’d have machine guns out to get them, but these people can take over the city, look at what they’ve done to businesspeople that have spent years and years building their business, and now they’re wiped out. Take it away. Governor Inslee ought to get his act together, get in there.”

ABC News’ Katherine Faulders and Morgan Winsor contributed to this story.