Authorities are digging into the social media accounts of Ricky Shiffer, the man armed with an AR-15 style rifle who attempted to break into the Cincinnati FBI office, Fox News confirmed Friday. 

Shiffer is suspected of posting extremist views on several social media platforms including Truth Social, a social media platform created by the Trump Media & Technology Group, in which he encouraged his followers to "kill the F.B.I. on sight."

The 42-year-old, who reportedly wore body armor while armed with an AR-15 style rifle and nail gun, was shot and killed after he ended the pursuit by pulling over and engaging in a six hours-long standoff in a rural field in Wilmington, Ohio.

ARMED MAN WHO TRIED TO BREACH FBI OHIO OFFICE KILLED AFTER SIX-HOUR STANDOFF WITH POLICE

Agents of the Federal Bureau of Investigation

FBI agents approaching a crime scene (Getty Images)

Shiffer is believed to have made a post on his Truth Social account 30 minutes into the standoff, during which he admitted to the attack.

"Well I thought I had a way through bullet proof glass, and I didn’t. If you don't hear from me, it is true I tried attacking the F.B.I., and it'll mean either I was taken off the internet, the F.B.I. got me, or they sent the regular cops while," a post by @RickyWShifferJr on the social media site said. 

The Thursday incident came after the FBI executed a search warrant at former President Donald Trump Mar-A-Lago house Monday.

The account bearing Shiffer's name then took to the social media platform in a "call to arms" Monday and said, "this is your call to arms from me."

"Leave work tomorrow as soon as the gun shop/Army-Navy store/pawn shop opens, get whatever you need to be ready for combat," the post continued. "We must not tolerate this one."

The message claimed, "They have been conditioning us to accept tyranny and think we can’t do anything for 2 years. This time we must respond with force."

Donald Trump's Mar-a-Lago

Former president Donald Trump's Mar-a-Lago resort in Palm Beach, Florida.  (Charles Trainor Jr./Miami Herald/Tribune News Service via Getty Images)

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In response to one question that asked, "Are you proposing terrorism?" the account bearing his name said, "No, I am proposing war."

Fox News has verified the posts and law enforcement are working to confirm who owns the account. 

In a comment to Fox News the Trump Media & Technology Group said, "Truth Social does not tolerate violent threats or incitement on our platform. We work to immediately remove any such posts from Truth Social and cooperate with law enforcement."

The social media platform removed the posts and the account after the suspect was identified. 

Truth Social is not the only social media site investigators are looking into.

FBI Cincinnati Field Office

Investigators outside the FBI Cincinnati Field Office after an armed suspect showed and fled the scene. (WXIX)

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The New York Times has also reported that Shiffer appeared in a video posted to Facebook from a pro-Trump rally in D.C. on January 5th. 

A Twitter account reportedly with his name also reportedly claimed that he attended the January 6th storming of the U.S. Capitol and expressed support for the Proud Boys, though Fox News has not independently verified the posts as his accounts appear to have been removed.