The Gainesville Police Department arrested Mason Scott Beuning, 18, for petit theft Tuesday afternoon at the Wal-Mart near Waldo Road.
Police said Beuning stole $36.96 worth of metal BBs, pellets, a flashlight and a set of flares, a misdemeanor charge.
Later in the afternoon, he told police he also had a homemade cardboard firework with black powder inside at his home. A fuse was attached to the sealed ends, according to his arrest report.
The Alachua County Sheriff’s Office arrived at Beuning’s home, removed the device, x-rayed it and confirmed four ounces of powder inside.
Beuning told police he had made the device a few years prior but had been afraid to detonate it. He is being held at the Alachua County Jail on $45,000 bond.
“Investigators will still be following up with the case to see if there’s any additional materials that could be used for explosives by Mr. Beuning,” GPD spokesman Ben Tobias said.
Elle Newbold contributed reporting.