A role-playing exercise by Punta Gorda, Fla., police designed to show the public how officers have to make tough, split-second decisions ended tragically as a 73-year-old former librarian was mistakenly shot and killed by an officer firing live ammunition.

A state investigation is underway to determine why a live round was used when police say they thought only blanks were available for the demonstration.

According to The Associated Press, Punta Gorda Police Chief Tom Lewis said the officer has been placed on administrative leave.

"We were unaware that any live ammunition was available to the officer," Lewis said at a news conference Wednesday. "The officer involved is grief stricken. We've got officers assigned to him to make sure he's psychologically stable."

The officer was identified as 28-year-old Lee Coel, with the police department for two years, who has participated in several of the "shoot/don't shoot" scenarios for the public.

The victim is Mary Knowlton, who was selected at random for the role-play at an event sponsored by the police and the Punta Gorda Chamber of Commerce. The citizens academy was attended by 35 people, including Knowlton's husband and Chief Lewis.

Chamber President John Wright told the News-Press.com immediately after the fatal shooting the audience didn't realize that Knowlton actually had been shot.

"Even when it started to play out people thought it was part of the theater of it," Lewis said. "Nobody knew the severity until they told us to move back, about 2 to 3 minutes."

Steve Knowlton, son of Mary Knowlton, said his mother was supportive of the police and that was why she and her husband attended the event. "I know this officer didn't mean for this to happen and I'm sure he's in a living hell right now. We all forgive him," said Knowlton.

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