Two teenage girls have been arrested after horrifying footage emerged of a 13-year-old girl being punched and kicked at a Melbourne beach earlier this month.
Detectives arrested two 15-year-old girls after the victim was allegedly assaulted near a toilet block close to Mordialloc Pier about 1.30pm on December 17.
Footage showed the victim being stomped on, kicked and hit while she was on the ground.
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A man in his 50s intervened and stopped the alleged assault, and the two girls left the area, police said.
The victim suffered minor injuries.
The two 15-year-olds were interviewed by police and released pending further enquiries.
Investigators are looking to speak to anyone who witnessed the alleged assault or those with dashcam or CCTV footage near the scene.
Detectives would also like to speak to the good Samaritan who helped the victim.
The investigation remains ongoing.
Police swarmed Mordialloc Beach over two days last week, when sweltering conditions saw hundreds of teenagers flock to the shore.
The gathering quickly got out of hand as the teens allegedly stormed a Woolworths store, pulling stock off the shelves, stealing and terrorising staff and shoppers.
Police used capsicum spray on members of the crowd as they allegedly clashed with officers, throwing glass bottles.
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