St. Felix told police that he was "fed up" with the GOP and that he hadn’t taken his medications when he posted the threat, the Herald reported.
On Tuesday, St. Felix was ordered held on $500,000 bail and told to have no contact with Diaz, according to NBC 6 in Miami. Before his arrest, he was out on bail for threatening another public servant along with burglary, prosecutors said.
During the court appearance, his attorney said St. Felix has a mental health issue.
Diaz, 37, is preparing for a primary election on July 25 for the state Senate seat vacated by Frank Artiles, who resigned in April after a tirade that included vulgar and racially charged comments about other senators.