Killer still on loose after Vic gang brawl

More than six weeks after a teenager was killed in a gang brawl in Melbourne's western suburbs, no one has been charged over his death.

Detectives are appealing to the public to help solve the fatal stabbing of 17-year-old Aguer Akech during a brawl at Keilor Plains railway station in the early hours of December 22.

The fight between up to 30 teenagers and men aged in their early 20s is believed to have been over a silver 2005 Holden Commodore sedan.

The gangs were armed with weapons including sticks, fence posts and knives for the melee which police believe was arranged earlier.

It followed a fight the day before at a soccer tournament at Green Gully Reserve.

Police said Aguer fled with others after he was assaulted but collapsed on Regan St and died at the scene.

Ten people were arrested but all were released without charge.

Detectives have released images and CCTV footage of males who were around the train station at the time in the hope that someone will recognise them.

"At this stage we don't know if any of the males in the CCTV were involved in the fatal stabbing," Detective Inspector Tim Day said in a statement on Tuesday.

"Because they were in the vicinity of the station at the time of the incident it's possible that they were part of either group involved, or they may simply be valuable witnesses for our investigation.

"Either way, it's crucial that we identify these people and speak to them."