Allegedly, a 29-year-old Florida man fired a flare gun at three people in another boat in Boot Key Harbor, the Monroe County Sheriff’s Office says.

Joseph Thomas Gaston, a liveaboard, was arrested Thursday and faces three counts of aggravated assault. No serious injuries were reported.

According to the Sheriff’s Office, a Florida Keys’ woman brought her 17-year-old son to the Marathon substation on Aug. 27 to report the incident, which happened around 3:30 that morning. The teenager told investigators he was tarpon fishing with a 15-year-old boy and a 27-year-old man when they returned to Boot Key Harbor to find his mother’s sailboat missing.

The trio found the sailboat adrift near Boot Key Bridge with its anchor lines cut with a knife. The three of them were securing the boat when Joseph Gaston and a woman arrived in a a dinghy.

The 17-year-old said he accused Gaston and the female of cutting the anchor lines, and after words were exchanged, the boy says Gaston fired a flare gun at him and the two others.

The boy told deputies that he used a sail to block the flare.

Investigators say those events were corroborated by the other two people on the boat and another man who told a detective that Gaston told him about shooting the flare at the teenager.

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