ST. AUGUSTINE, Fla. -- A teacher at St. Joseph Academy Catholic High School in St. Augustine has resigned after a gun was found in his backpack on school property, officials said.

The science teacher at the private school was placed on administrative leave but has since resigned, Kathleen Bagg with the Diocese of St. Augustine told First Coast News Thursday.

A letter was sent to parents to inform of the incident, Bagg said.

First Coast News has chosen not to name the teacher since he has not been criminally charged.