A TEENAGE boy has died after being "king hit" while partying at a Halloween theme night in Melbourne.

Justin Galligan, 16, had been on life support since Saturday after suffering a serious brain injury in a brawl that erupted when youths tried to gatecrash the Balwyn North party on Friday night.

He died about 4.30pm yesterday.

Police say the party turned ugly when a group of youths arrived at the property's back fence, and a fight broke out in a car park metres away.

Police are investigating what provoked the fracas between the guests and the gatecrashers, about 11.30pm.

More than 15 people, aged between 15 and 17, were involved in the brawl.

Police believe Justin was knocked out by a punch and hit his head on the ground, but regained consciousness.

It's understood that guests, including Justin, then returned to the party, where alcohol was being consumed.


The group dispersed shortly afterwards, and some time later Justin was driven home to Fairfield and went to bed.

But the next morning his parents were unable to rouse him and he was taken to the Royal Melbourne Hospital.

Police yesterday appealed to any of the 50- plus guests at the party whom they have not interviewed to come forward.

Justin, a gregarious junior footballer, went to Kew High School. Some other guests were from exclusive schools in Melbourne's inner-east.

"It's an absolute tragedy," Det. Sgt Graham Guy said.

"It's vitally important to us to piece together what happened, for his parents.

"I'm at a loss to explain why teenage boys of this calibre would want to get involved in things like this.

"I think it just highlights how a situation can turn fatal. It doesn't take much at all. I think people need to realise it can happen in a split second.

"The parents that held the party did their utmost to control it, so I wouldn't expect much more from them," Det. Sgt Guy said.

Randy Bowden, who with his wife Christine was supervising the party, said he was "deeply distressed" for the teenager and his family.

But he said gatecrashers did not enter the party.

"Heartbroken is not enough, distressed is not enough to describe this," he said. "We feel deeply distressed for the family. I don't have the words."

Andrew Hodson, whose son knew Justin, said he was stunned by the tragedy.

"He was beautiful. He was my son's age. At the end of the day, he's a baby," he said.