Jon Alexander, Missouri Liquor Store Clerk, Veteran, Pulls Gun on Armed Robber (VIDEO)

An armed man attempting to rob a Missouri liquor store had no idea what he was up against.

Caught on surveillance footage making the rounds this week, a Marionville store clerk named Jon Lewis Alexander successfully stopped a would-be thief by calmly pulling out his own gun and scaring away the suspect.

Alexander is not your average store clerk: He is apparently a four-tour Iraq War veteran who also worked as a prison guard and once helped extradite federal prisoners.

See also: Concealed-Carry Permit Holder Fires Shots at Five Men Trying to Rob Him

As is pretty clear in the video, Alexander, 54, was unfazed by this attempted robbery.

See for yourself, via the Associated Press' raw footage:

The incident happened at a Beer 30 store in southwest Missouri.

Alexander reportedly used a Walther PPX 9 mm handgun, which he clearly pointed straight at the mouth of the suspect, who shortly thereafter fled.

Garry Earnest, deputy chief with the Aurora Marionville Police Department, tells Daily RFT this morning that police believe they know the identity of the suspect, but have not yet issued charges or taken the man into custody.

He says that it can be dangerous not to comply with armed robbers looking for cash, but adds, "Since the person pointed a weapon at him, he had a right to defend himself."

Here's the News-Leader's account of the incident from an interview with Alexander:

The man came in the store smoking a cigarette, and Alexander said he quickly explained that was against the rules. Within seconds, the man in a gray T-shirt was at the counter, demanding "all the (expletive deleted) money."

In less than three seconds, as Alexander threw out a couple of expletives of his own and threatened to "blow his (expletive deleted) head off," the man is seen in the video backing away, his own firearm still at his side.

"He didn't even bother holstering his weapon" as he quickly left the store, Alexander said.

The store owners generally don't allow employees to be armed, according to the AP, but Jeannine Dawson, who runs the business with her husband, apparently made an exception for Alexander.

She said, "From what I have known of Jon, that handgun is kind of a part of him, like my handbag is to me."

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