Federal authorities announced charges Friday against a Pennsylvania man they accused of threatening to assassinate President Trump and vowing to slaughter immigration officers at ICE.

The FBI said Shawn Monper obtained a firearms permit soon after Mr. Trump’s inauguration and bragged online that he’d bought a gun a month and stockpiled ammunition and bought body armor, amid his threats.

“We just need to start killing people, Trump, Elon [Musk], all the heads of agencies Trump appointed and anyone who stands in the way,” the FBI said Mr. Monper posted to YouTube using an account under the name “Mr. Satan.”

During Mr. Trump’s address to Congress last month, the FBI says Mr. Monper posted that he was “gonna assassinate him myself.”

And on April 1, he declared: “If I see an armed ice agent, I will consider it a domestic terrorist, and an active shooter and open fire on them.;/

The Washington Times has sought comment from Mr. Monper’s lawyer for this story.

He is being detained pending a hearing next week.

The charges follow less than a week after federal prosecutors charged a Texas man with threatening Mr. Trump and U.S. Immigration and Customs Enforcement personnel, calling them the “Gestapo.”

Robert Wilson King named one of his social media accounts “Die Trump,” the FBI said in documents in that case.

• Stephen Dinan can be reached at sdinan@washingtontimes.com.