The "Twilight" star was captured on video Monday lashing out at a photographer who was, naturally, following her around while she waited to be picked up behind a building in Los Angeles.
In a clip of the incident posted by TMZ, the photographer can be heard asking Stewart, "Why are you saying [expletive] off?"
"Because you are piece of [expletive] and you don't deserve to breath the same air I do," the 23-year-old actress responds.
Seconds later, Stewart is seen emerging from behind a wall and getting into a car.
As TMZ points out, the "Snow White and the Huntsman" star was already angry when the cameras began rolling. The reason behind her anger, however, remains a mystery.
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