The newspaper linked the suspect, who was killed by police, to an unverified Twitter account that claimed he "was there" on Jan. 6.
The account told Rep. Marjorie Taylor Greene (R-GA) "It's over. The next step is the one we used in 1775."
And tweeted, " "Save ammunition, get in touch with the Proud Boys and learn how they did it in the Revolutionary War, because submitting to tyranny while lawfully protesting was never the American way. LEXINGTON."
The suspect may have also had an account on Truth Social.
"Looks like Truth Social just deleted the account suspected to be that of the man who attacked the FBI office in Cincinnati," USA Today correspondent Will Carless reported.
"If this is Shiffer's Truth Social account, he posted two days ago about killing federal agents, and posted 8 hours ago about attacking the FBI," Carless reported.
NBC News reported, "Shiffer appeared to have posted a message detailing his failed attempt to gain entry to the FBI building."
Extremism researcher Jared Hold reported on the post in question.
"Well, I thought I had a way through bulletproof glass, and I didn't," the account posted.
"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," the post trailed off.
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