A retired veteran Jacksonville sheriff’s officer was injured Wednesday morning during a training exercise when a member fired a gun loaded with marking rounds at him, according to the Sheriff’s Office.

Chip Williams was training 10 officers at the Criminal Justice Center next to Florida State College of Jacksonville on Capper Road when the incident occurred. Director Tom Hackney said Williams was working with a corrections officer in a use-of-force training event.

“One of the students involved in this went up and took the blank gun … from the instructor’s waistband and placed that against the instructor’s back and fired,” Hackney told Jacksonville.com. “There is no projectile in that. It is just a blank. But it is gunpowder.”