A young woman repeatedly screamed ''Oh my god, he's dead,'' when she saw a man lying on the ground on a train platform.

Fairfax Media has obtained dramatic CCTV and video footage of an alcohol-fuelled attack at Corrimal railway station in Wollongong in July last year that landed one man behind bars and left two others with jail sentences hanging over their heads.

The 17-year-old victim survived, suffering only a broken jaw, despite being repeatedly punched, kicked and stomped on.

The group's ringleader and the main aggressor, Karl Greenland, 18, was sentenced to a minimum of 12 months' jail, while his co-accused, Joshua Gillings, 21, and a third man who cannot be named for legal reasons, received suspended prison sentences.