Casey Garlick was taken into custody Tuesday for the Jan. 13 holdup of the Pet Supermarket in Casselberry, the Orlando (Fla.) Sentinel reported.
A police report released Wednesday said Garlick allegedly walked into the pet store and handed a clerk a note demanding money.
The note claimed he was armed with a syringe tainted with his HIV-infected blood.
"The note also claimed that he was in possession of a bomb," the report stated. "Garlick fled the scene with several hundred dollars."
Police seized a syringe from Garlick when he was arrested, the newspaper reported.