Police have arrested a 27-year-old man after a large brawl broke out in Melbourne's west early this morning.

Officers say more than 80 people were involved in the fight outside a function centre in Albion, where crowds had gathered to celebrate Liberia's independence day.

"People at the party informed us that... people from another African country had attended the scene and caused the trouble," Sergeant Mick Downe said.

Two men were rushed to Sunshine Hospital, one with facial injuries and the other with a stab would to his chest.

He has since been taken to the Royal Melbourne Hospital and is in a serious condition.

Police arrived at the site at 3am but the fight was already over and the crowd had largely dispersed.

"No units were able to attend at the time because there was no units available... (we) had to get units from the city to come," Sergeant Downe said.

"The units attended en masse, about 15 units, the fighting had stopped at this stage."

He said police were not aware that the function was on.

Police arrested a 27-year-old man from Western Australia who is helping with their investigations.

Anyone with information is urged to contact CrimeStoppers on 1800 333 000.