Gossip site TMZ are reporting that the 22-year-old actor confronted a man he thought had thrown a rock at him and his friend after leaving a bar in Philly during the early hours of Sunday morning.
The video footage shows the Aussie actor punching the victim in the head while Hemsworth's friend holds the victim down. The victim was clinging to Hemsworth's leg at the time.
Police showed up after the few punches were thrown, dispersing the fight and onlookers.No charges have been laid yet, and Hemsworth and his friend are thought to have left the scene when the officers arrived.
Hemsworth, who most recently starred in "The Hunger Games", is engaged to singer/actress Miley Cyrus. He's currently shooting Aussie director Robert Luketic's film "Paranoia" in Philadelphia alongside Harrison Ford.
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