Florida police announced Saturday that they arrested a man who allegedly warned people to stay away from Walmart next week and that he would be getting back his AR-15 gun.

Richard Clayton, 26, was arrested after allegedly posting the threat on Facebook, the Florida Department of Law Enforcement announced Saturday.

Investigators said Clayton “appears to believe in the white supremacist ideology” and said he had a history of posting threats on Facebook with fictitious accounts. ADVERTISEMENT

An investigation began on Aug. 6 after Clayton allegedly posted the threat to Facebook, the department said.

“3 more days of probation left then I get my AR-15 back. Don’t go to Walmart next week,” police say Clayton wrote.

His arrest comes one week after 22 people were killed in a mass shooting at a Walmart in El Paso, Texas. The suspected shooter is alleged to have posted an online manifesto ahead of his attack warning of a “Hispanic invasion.” The suspect reportedly told police he was targeting "Mexicans."

The FBI has said the majority of domestic terrorism cases investigated since October were tied to white supremacists.