BRAD PITT opens can of whoop-ass for vicious punk SHIA LaBeouf!

Usually mild-mannered BRAD PITT exploded on the set of his new WWII flick “Fury” when co-star SHIA LABEOUF – the evil-tempered loony I called “Hollywood’s next creepy crash-and-burn” after he got his mouthy butt kicked for triggering a 2011 Vancouver bar brawl – suddenly smashed Brad in the kisser with the smoking-hot barrel of a machine gun!

Filming in Oxfordshire, England, playing two tough GIs battling Nazis, Brad and Shia were aboard a combat-ready tank when Shia “became a bit too intrigued by the machine guns in the tank’s turrets and started firing the guns wildly between scenes,” reports My SpyWitness.

“The guns were loaded with blanks, not real bullets, but Brad was NOT happy with Shia goofing around. He tapped him on the shoulder, meaning to caution him, but Shia whipped the gun turret around and hit Brad smack in the face with the hot barrel! Brad, livid, yelled, ‘Quit f****** around!’ Everyone froze, but Shia started laughing – and Brad just snapped! He lunged – and crew members literally had to pull him off the jerk. Shia yelled, ‘Hey, man, what’s your problem?’ Bellowed Brad, ‘I have 5-year-olds more mature than you!’” Brad then asked for a timeout so he could calm down, and left the set, as did Shia.

Said the source: “Later, they both returned, and Shia – looking very sheepish – turned to Brad and asked: ‘Are we good?’ They shook hands and we’re happy to report there’ve been no further altercations!”

UPDATE: After picking that 2011 Vancouver fight and being detained by LA cops for another 2011 brawl at the aptly-named Mad Bull’s Tavern, Shia exited the Broadway play “Orphans” earlier this year – after angrily punching through a door at rehearsals; and he just got kicked in the groin on a London street for filming two vomiting women. WOW! Stay tuned.

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