iStock/Thinkstock(WASHINGTON) — Continuing his drumbeat messaging campaign on immigration just days before the midterm elections, President Donald Trump, in remarks at the White House Thursday, announced what he described would be a change to rules to crack down on asylum seekers, suggesting without clear evidence that many migrants seek and receive asylum illegitimately.

Trump said the White House is finalizing plans to require migrants to “present themselves lawfully at a point of entry,” and that he would sign a “comprehensive” executive order “sometime next week.”

Under current law, immigrants may apply for asylum regardless of how they enter the country. Trump’s said his order would require them to apply at a port of entry.

For the first time, Trump also seemed to threaten the use of force against migrants at the border.

“They’re throwing rocks viciously and violently,” he claimed, referring to an encounter between the migrants and Mexican police. “They want to throw rocks at our military, our military is going to fight back.”

Asked if the military troops being sent to the border might fire on migrants, Trump responded, “Anybody throwing rocks … we will consider that a firearm.” Trump said, although the thousands of troops sent to the border will not be acting in a law enforcement capacity, and have been deployed to provide logistical support. They maintain the right to use firearms for self-defense, according to the Pentagon.

No country can allow itself to be “overwhelmed by masses of people rushing our border,” Trump said.

He urged migrants in the caravan traveling towards the U.S. – Mexico border to “turn back now,” again likening the dwindling procession still approximately 900 miles away from the border to an “invasion.”

“These are tough people in many cases,” Trump said, adding that the caravan of men, women and children is full of “young men, strong men” who are “not legitimate asylum seekers,” again providing no evidence to back up that claim.

“Asylum is not a program for those living in poverty,” he said. “Asylum is a very special protection intended for those fleeing government persecution.”

Trump repeated comments made in recent interviews that migrants seeking asylum will be kept in tent cities, rather than released until their cases are adjudicated in immigration court. Trump said “we’re putting up massive tent cities” with “the military’s help” although the Pentagon said earlier this week that it had received no request to set up tents for detained migrants.

The president also made a number of false claims, suggesting that the Obama administration, and not the Trump administration, separated families at the border, that most asylum seekers don’t show up for their court dates, a claim debunked by PolitiFact, and that Democrats want migrants to vote and to sign them up for free health care, welfare and education, a claim also contradicted by PolitiFact.

The president’s remarks came just before he headed to another campaign rally as part of a pre-election blitz, this one in Columbia, Missouri and after he has also called for ending birthright citizenship and sending thousands of additional troops to the border as a caravan of migrants makes its way toward the United States from Central America.

The president has made immigration the centerpiece of his closing argument ahead of Tuesday’s midterm election.

“Republicans want strong borders, no crime, no chaos, and no caravans. Democrats want open borders, and they want to invite caravan after caravan into our country, which brings crime upon crime,” Trump said at a campaign rally in Fort Myers, Florida, on Tuesday.

After denying that his heated rhetoric over immigration is fear mongering before voters head to the polls to ABC News’ Mary Bruce, the president tweeted a controversial and racially-charged video produced by the White House depicting some illegal immigrants as murderers.

In addition to increasing the presence of U.S. Army National Guard troops on the border, the president has called for ending birthright citizenship. Trump claims birthright citizenship is not enshrined in the 14th Amendment of the Constitution, but many legal scholars and Republican lawmakers — including House Speaker Paul Ryan — disagree.

The president lashed out at Ryan over voicing his criticism of ending birthright citizenship.

“The Democrats want to continue giving automatic birthright citizenship to every child born to an illegal alien,” Trump said. Even if they’ve been on our soil for only a matter of seconds, hundreds of thousands of illegal immigrant children are made automatic citizens every year because of this crazy policy, and they are made instantly eligible for every privilege and benefit of American citizenship at a cost of billions of dollars a year.”

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