VIDEO: Oh my god he's dead: witness's anguish

It begins with an aggressive confrontation and ends with a young man struggling to get to his feet after a savage beating.

Seconds before, as the man lies motionless, a young woman repeatedly screams "Oh my god, he's dead".

The Mercury has obtained dramatic CCTV and video footage of an alcohol-fuelled attack at Corrimal railway station in July last year that landed one man behind bars and 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 12 months' jail, while his co-accused, Joshua Gillings, 21, and a third man who can't be named for legal reasons, both received suspended prison sentences.

The 2½-minute video, tendered to Wollongong District Court this week as part of the police case against Greenland and Gillings, clearly captures the brutal assault from start to finish.

A still from footage of the alcohol-fuelled attack at Corrimal railway station in July.

A still from footage of the alcohol-fuelled attack at Corrimal railway station in July.

Made up of both CCTV footage from the train station and a mobile phone video shot by an onlooker, the video begins with a large group of teens yelling out towards the victim and his friend while they wait on the eastern platform.

Seeking a fight, the group moves from outside the station onto the platform and confronts the two men, who begin to retreat backwards.

A fight breaks out between the victim and Greenland and the crowd surges forward around the pair.

Gillings and the third co-accused join in on the attack, laying several punches and kicks to the victim's head and torso, until he loses consciousness.

Greenland is then seen to jump in the air and stomp on the victim's head.

The crowd disperses, leaving the teen lying motionless on the platform.

The video ends with images of the victim staggering towards a nearby seat, falling over as he tries to right himself.

Presiding judge Paul Conlon this week described the attack as "brutal and cowardly".

CCTV and a shot from a mobile phone video show the sequence of events.

"Such assaults where thuggery and cowardliness are involved are all too prevalent in our society," he said, adding the potential for severe injury to the victim was "extreme".

Judge Conlon accepted that Greenland had instigated the fight, saying the video footage clearly showed the victim retreating under the threats.

"There was nothing done by the victim that could be said to have provoked [Greenland]," he said.

He also accepted that Gillings had played a lesser role in the assault.

The court heard the victim and Greenland had been at the same house party in Corrimal on the evening of July 14. However, when it was shut down, the teen and his friend walked to the train station intending to return to Dapto and were accosted by the group just after midnight.

The victim was taken to Wollongong Hospital before being transferred to St George for jaw surgery.

Greenland and the 17-year-old co-accused were arrested two days later at Bellambi, while Gillings was charged last August.

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