A 26-year-old Florida man was arrested Friday after investigators discovered a threatening message on Facebook that suggested he was planning a shooting at a Walmart store.

The Florida Department of Law Enforcement said that its agents arrested Richard D. Clayton of Winter Park, Florida, for written threats to kill or do bodily harm.

The arrest was the result of a joint investigation by the FDLE, FBI’s Joint Terrorism Task Force and the Winter Park Police Department, according to a news release. The authorities launched their joint investigation on Tuesday after the suspect posted a threatening message to Facebook.

“3 more days of probation left then I get my AR-15 back. Don’t go to Walmart next week,” Clayton wrote on Aug. 6.

The online threat came only days after 31 people were killed in two mass shootings in Texas and Ohio last weekend. One of those shootings, which left 22 people dead, occurred at a Walmart in El Paso, Texas, on Aug. 4.

Investigators said that Clayton appears to believe in white supremacist ideology and has a history of posting threatening messages to social media using fake accounts.

Orlando-based TV station News 6 reported that Clayton made his first court appearance on Saturday, where his bail was reduced from $25,000 to $15,000 on the condition that he stays at least 1,000 feet away from any Walmart.