A search warrant was executed at Reardon's parent's home the same day local police received the tip about the video. Reardon was arrested without incident.
"Grateful for the work of the FBI, local law enforcement and our community partners in the Youngstown Jewish community," the Anti-Defamation League's regional office in Cleveland tweeted Saturday. "We will continue to employ all our resources to stop the spread of white nationalism and violent extremism.
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The organization continued: "Although there is no continued active threat to the community, we ask that people remain vigilant, and if you see something, please contact law enforcement immediately."
The FBI did not describe what was found during the search of Reardon's parent's house.
"This is considered an ongoing investigation, further details can not be released at this time," the FBI said in the release.
Reardon is being held in the Mahoning County (Ohio) Jail on $250,000 bond and is scheduled to appear in court Monday in Mahoning County.
A message from USA TODAY seeking comment from the New Middletown Police Department in Ohio — the arresting agency in this case — was not immediately returned.
