President Donald Trump stressed on Twitter that he has ordered the Department of Homeland Security to take extreme measures to screen foreign visitors to the U.S. after a fatal terrorist attack in New York City Tuesday evening.

The president has pushed an extreme vetting program for immigrants since he took office earlier this year. After what is being called the deadliest terrorist attack on New York City since 9/11, the president appears to believe that more aggressive measures are required.

I have just ordered Homeland Security to step up our already Extreme Vetting Program. Being politically correct is fine, but not for this!

— Donald J. Trump (@realDonaldTrump) November 1, 2017

Trump has repeatedly tied immigration to radical Islamic terrorism on American soil, a link that was demonstrated by Tuesday’s attack. The 29-year-old attacker — Sayfullo Saipov — was a green card holder from Uzbekistan. Authorities found a letter in Arabic at the scene that appeared to indicate the terrorist is loyal to the Islamic State.

The extremist drove a rented van into civilians, killing eight. Six died at the scene, while two more passed away at the hospital. A number of others were severely injured in the attack.

The White House has not yet clarified what the president has in mind to make America more secure, but he has made it clear that ISIS and other radical extremists will not be allowed to spread terror in the U.S.

We must not allow ISIS to return, or enter, our country after defeating them in the Middle East and elsewhere. Enough!

— Donald J. Trump (@realDonaldTrump) October 31, 2017

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