Shoplifting Suspect Pulls Gun on Police Officer at Walmart, on Video

What started out as alleged shoplifting turned into attempted murder when an Ohio man pulled a gun on a police officer inside a Walmart Thursday ... and the whole thing was caught on tape.

Watch this insane video ... 21-year-old Shane Newman appears anxious, chewing on his gloved fingers while sitting inside Walmart's loss prevention office around 1:40 PM. You can see him sneakily turn his back to the camera, and when he turns back around ... he produces a gun.

While aiming the weapon at an officer off-camera, you can hear what appears to be the click of Newman pulling the trigger, but the gun never goes off.

Then, all hell breaks loose. The store's loss prevention specialist dives on Newman, knocking the gun out of his hands, before the officer rushes in with a crushing knee to Newman's midsection. Newman is then quickly wrestled to the ground.

WOIO reports Newman was not allowed to own or have a firearm due to a previous felony conviction. They also report he was in possession of 50 blue pills identified as Molly -- AKA  MDMA. Police said an officer found two rounds of 9mm ammunition in Katrina's pocket.