Updated
NEWYou can now listen to Fox News articles!

Florida congressional write-in candidate and former U.S. Marine William Upham was arrested Wednesday after posting a video calling President Donald Trump "the Antichrist" and saying the president "must be killed."

Federal prosecutors on Thursday charged William L. Upham, 35, with threatening the President of the United States after authorities say he posted multiple videos urging violence against Trump. 

Upham appeared in federal court in Jacksonville and was ordered detained pending further proceedings, according to the Justice Department. If convicted, he faces up to five years in federal prison.

Upham, a Republican write-in candidate for Florida's 5th Congressional District who describes himself on X as a prosecutor "running to fix a broken political system," opens the nearly seven-minute video by saying he entered the race to restore bipartisanship, return power to the working class and "fix our broken political system."

TWO YEARS AFTER BUTLER, THREATS AGAINST TRUMP KEEP ASSASSINATION ATTEMPT IN SHARP FOCUS

Composite image showing former U.S. Marine and Florida congressional candidate William Upham next to President Donald Trump speaking at a podium.

Former U.S. Marine and Florida congressional candidate William Upham posted a video calling President Donald Trump "the Antichrist" and saying he "must be killed," prompting condemnation from the Marine Corps and a response from the U.S. Secret Service. (X/@uphamforflorida/Photo by Anna Moneymaker/Getty Images)

The tone quickly shifts, however, as Upham says he has come to believe the country is "broken" and that America is engaged in a spiritual battle.

"We are led by a president who is the enemy of God," Upham says before citing Bible passages and discussing the oath he took as a Marine officer to defend the Constitution "against all enemies, foreign and domestic."

🚨 Know something we should investigate?

📩 stepheny.price@fox.com

📸 IG: @fndstephprice

🎥 X: @StephenyPrice

Your tip could lead to our next story.

He then claims there is "no doubt" Trump is "the Antichrist."

"He is a false messiah. And he is your enemy. And he must be killed," Upham said.

According to the criminal complaint, investigators reviewed another video in which Upham allegedly described his message as "a call to arms" and urged viewers to overthrow the Trump administration. 

Prosecutors say Upham recommended using a semi-automatic rifle, such as an AR-15, and instructed followers that the "enemy" should be killed with "two shots to the chest" and "one shot to the head."

BUTLER MAN’S ONLINE RANTS TO KILL TRUMP END IN GUILTY PLEA AFTER FBI PROBE

Donald Trump in Oval Office

A Florida congressional candidate and former Marine is facing backlash after posting a video calling President Donald Trump "the Antichrist" and saying the president "must be killed." (Saul Loeb/AFP via Getty Images)

Federal investigators also allege Upham later emailed a reporter that he made the videos "to declare war against President Trump on behalf of God" and that he would "kill President Trump at the time that God chooses." 

The complaint further alleges Upham wrote that the country "must overthrow President Trump by the violent use of force and kill him."

The U.S. Marine Corps quickly condemned Upham, saying he was medically discharged May 30, 2025.

"The Marine Corps is aware of the disturbing statements made by William Upham," the service wrote on X. "The comments made by Upham are a direct violation of the oath he swore to uphold and are not in keeping with the service's values."

TRUMP FACES UNPRECEDENTED THIRD ASSASSINATION ATTEMPT

U.S. Marines patch on uniform.

William Upham referenced the oath he took as a Marine officer while making the remarks, prompting the Marine Corps to condemn his comments and stress that he was medically discharged in May 2025. (Kevin Carter/Getty Images)

The U.S. Secret Service also acknowledged the comments in a statement to Fox News Digital.

"The U.S. Secret Service is aware of the comments made by a congressional candidate in Florida, and we investigate anything that can be perceived as a threat toward one of our protectees," a spokesperson said. "Out of concern for operational security, we do not discuss matters of protective intelligence."

CLICK HERE TO DOWNLOAD THE FOX NEWS APP

Acting Navy Secretary Hung Cao also condemned the remarks, writing on X, "Unacceptable. William Upham is no longer a Marine and does not represent our values or ethos."

Fox News Digital reached out to the FBI, the White House and Upham's campaign for comment.