A Florida teen was arrested after he allegedly stole an AR-15 and tactical gear from an unmarked Palm Beach Sheriff’s deputy’s vehicle, officials said Sunday.

A 17-year-old of Boynton Beach, flaunted the stolen weapons on an Instagram live stream as he danced to rap music, the Miami Herald reported, citing a probable cause affidavit.

The deputy reporting the items stolen to Boyton Beach police on Aug. 14. He left his unmarked cruiser parked at a shopping plaza for hours, according to the newspaper. He allegedly stole two loaded magazines, a gas mask, Taser, ballistic helmet and rifle clips, police said.

The live stream he launched gave police ground for a search warrant, the Herald reported. Detectives found the stolen items under the teen’s mattress, police said.

He faces grand theft and burglary with a firearm charges and was being held at a juvenile detention center.