A Florida man allegedly wrote, "I'll kill Joe Biden today," on July 11, two days before Donald Trump survived an assassination attempt in western Pennsylvania. 

Jason Patrick Alday, a 39-year-old Florida man, has been on the Secret Service's radar since late June, when he told an intake officer of a mental health facility that he didn't like President Biden and was going to "slit his throat," according to a probable cause affidavit. 

Secret Service agents questioned him, and he denied the accusations, according to federal court documents. 

On June 30, Alday allegedly said on X that Biden's health is declining: "Not doing too good at all. Should I finish him off?"

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President Joe Biden

President Biden speaks at a campaign event in Atlanta. (Megan Varner/Getty Images)

That was one of four posts Alday allegedly wrote under the X username @Jman86628004 after his emphatic threat on July 11. 

"I'll kill joe biden today!!" he allegedly wrote, according to the affidavit reviewed by Fox News Digital.

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He allegedly taunted the Secret Service agent who questioned him in June in a series of racist tweets.

Secret Service agents stand by the presidential limousine as President Biden disembarks from Air Force One upon arrival at Raleigh-Durham International Airport in Morrisville, N.C., in January.

Secret Service agents stand by the presidential limousine as President Biden disembarks from Air Force One upon arrival at Raleigh-Durham International Airport in Morrisville, N.C., in January. (Saul Loeb/AFP via Getty Images)

There were multiple other bigoted tweets directed at the investigating Secret Service agent and graphic threats to kill the president, according to court documents. 

Alday was arrested on Monday by the U.S. Marshals Service Task Force and the Secret Service. 

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He was charged in federal court with engaging in sending threatening communications, making threats against the president and threats against federal officials.

He was detained after his initial appearance in Florida federal court.

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Biden ran political ads claiming Trump wants to be a "dictator." (Getty)

Two days before Alday was arrested, former President Trump was nearly killed by a gunman on a rooftop overlooking a rally in Butler, Pennsylvania. 

A bullet grazed Trump's ear and may have killed him if he didn't move his head at that exact moment. 

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A beloved fire chief and married father of two died shielding his family, and two others were critically wounded. 

The gunman, Thomas Matthew Crooks, 20, was "neutralized" after firing several times. 

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A motive remains unclear, and several unanswered questions have spiraled into conspiracy theories, and the Secret Service and local law enforcement blame each other.