The husband of a woman shot dead in front of 34 people in a police role play exercise gone wrong has recalled the horrifying moment his wife was killed.

Officer Lee Coel, 28, shot retired librarian Mary Knowlton by 'mistake' during the demonstration in Punta Gorda, Florida, on Tuesday night.

Mrs Knowlton's husband, Gary, said the 73-year-old mother had 'volunteered to be the victim in the mock shooting' that took her life.

'I was standing 10 feet away from her when the guy shot her,' Mr Knowlton told CBS Miami. 'I just can't believe she's gone, but I have to learn to live with that.'

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Gary Knowlton (right), the husband of Mary Knowlton (left), who was shot dead in front of 34 people during a police role play has recalled the horrifying moment his wife was killed

He also said the couple met in high school, and had been married for 55 years.

Mr Knowlton added that he does not blame Officer Coel, and said he knows the shooting was an accident.

'I think it's a whole series of errors. I can't control that stuff and I know there was no ill intent, just mistakes,' he told the network.

CBS Miami also showed footage from an excessive force complaint that was made against the officer in April 2013 while he worked in Miramar, Florida.

'She volunteered to be the victim in this mock shooting. I was standing 10 feet away from her when the guy shot her,' Mr Knowlton said

On Wednesday, police identified Coel (left) as the officer who accidentally shot and killed Knowlton (right)

Surveillance video shows Officer Coel dragging a suspect out of his police car by the ankles, forcing the suspect to land heavily on the asphalt after flying out of the backseat.

He was forced to resign from the Miramar Police Department just weeks later, CBS Miami reports.

Another video that was released on Thursday shows Coel's K9 mauling Michael Schumacher during an arrest in Puna Gorda.

Footage from an excessive force complaint that was made against Officer Coel in April 2013 while he worked in nearby Miramar has also been revealed

Surveillance video shows Officer Coel dragging a suspect out of his police car by the ankles, forcing the suspect to land heavily on the asphalt after flying out of the backseat

The cyclist was left with horrific injuries that left him hospitalized.

Attorney Scott Weinberg took the man's case in June, and that's when he viewed Coel's dashcam video of the arrest and informed local media of the footage.

He has said Coel should never have been allowed to become a cop.

Another video that was released on Thursday shows the moment Coel's K9 mauled Michael Schumacher while he was arresting him in Puna Gorda. Schumacher is seen in hospital

'I told everyone that this officer was dangerous and he needed to be fired,' Weinberg told Daily Mail Online.

'If he had been fired like he should have been when he ordered that dog to maul my client for a minute and 47 seconds, then this wouldn't have happened.'

Punta Gorda police have insisted Coel did not violate any of the department's policies during the canine arrest.

'I just can't believe she's gone, but I have to learn to live with that,' Gary Knowlton (left) said after his wife, Mary (right), was shot and killed by 'accident'

Police officer Lee Coel was captured as he accidentally shot and killed community volunteer Mary Knowlton, because he loaded his gun with live rounds instead of blanks. He was dressed as a 'criminal' during the role play incident where the tragic incident occured

It comes after footage of the moment the cop dressed as a 'bad guy' shot the 73-year-old mother dead during a role play exercise - because he loaded live rounds instead of blanks - was released.

The aim of the class was to teach people when not to shoot.

Officer Coel fired the fatal round while dressed in a gray hooded sweatshirt and black ski mask - in a bid to look like a 'criminal'.

Mrs Knowlton was picked from the audience to play the 'victim' during the scenario.

Mrs Knowlton is seen holding a gun just moments before she was shot dead during the 'shoot/don't shoot' exercise in Punta Gorda, Florida

Officer Coel (pictured), who has worked for the department since March 2014, has been been placed on administrative leave while the incident is investigated

Coel then shot her in the shoulder and the chest, thinking he was firing blanks. But when those watching saw blood, they knew something was wrong.

Her husband watched as volunteers turned her lifeless body over to reveal the horrific injuries.

John Wright told NBC News: 'We all thought that this was part of the theater, we all thought it was expected.

'When she went to the floor I think we all realized the severity of what we'd all witnessed.'

Mrs Knowlton (center) is pictured with her son Steve (left) and husband Gary (right) outside the White House

Knowlton's son, Steven (left), said it was a devastating time for the family in a statement released on Wednesday morning

Officer Coel, who has worked for the department since March 2014, has been been placed on administrative leave while the incident is investigated by the Florida Department of Law Enforcement.

In a statement, the police department said: ' Officer Coel is frequently seen throughout our community providing department presentations and tours and specifically role-playing in these shoot/don’t shoot scenarios as well as a police presence at youth and neighborhood events.

'Officer Coel remains on administrative leave while the investigation into this incident gathers more details into how this tragedy happened.

A woman is seen confronting a police officer during one of the simulated exercises

'Like the rest of our community, Officer Coel is devastated by what happened and is receiving assistance from our department and the Police Benevolent Association at this time.'

After the incident, p olice chief Tom Lewis said Knowlton had been chosen randomly from the group for a 'shoot/don't shoot' simulation during the Citizen Police Academy at the station headquarters.

Officer Coel, who was playing the role of a 'bad guy', was supposed to fire blanks at the 'victim' Knowlton, but live rounds were loaded in the gun instead.

Blank rounds (left) have groves in the top, while live bullets have more rounded tops

Knowlton's class met at the Punta Gorda Police Department around 5.30pm and the shooting occurred just before 7pm.

The demonstration 'used simulated lethal force' to teach the class about making critical decisions, WINK News reported.