Police patrol Mordialloc beach

Two teenage girls have been taken into custody following the circulation of shocking video footage showing a 13-year-old girl being violently attacked at a Melbourne beach earlier this month.

Authorities apprehended the two 15-year-old girls after the young victim was reportedly assaulted near a restroom area adjacent to Mordialloc Pier around 1:30 p.m. on December 17.

The disturbing video captures the victim being stomped, kicked, and struck while she lay on the ground.

Police patrol Mordialloc beach
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. (Joe Armao/The Age )

A man in his 50s intervened, putting a stop to the alleged attack, after which the two girls reportedly fled the scene, according to police statements.

The 13-year-old victim sustained minor injuries from the incident.

Following their arrest, the two teenagers were questioned by the police and subsequently released as investigations continue.

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.

Up to 200 teenagers turned up to Mordialloc Beach yesterday.
Police swarmed Mordialloc Beach over two days last week, when sweltering conditions saw hundreds of teenagers flock to the shore. (Nine)
Vision shows hundreds of young beachgoers storming the Woolworths store.
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. (Supplied)

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.