Police have been left puzzled after a 50-man brawl broke out at a Melbourne warehouse on Saturday night.

Police say around 30 men were enjoying an “after work” barbecue in the southwestern Melbourne suburb of Laverton North before they were approached by another group of about 20 men.

Detective Senior Constable Erin Hardie said police did not know what led to the fight. As of yet, no arrests have been made and the investigation is ongoing.

“At this stage we have no idea in relation to motive, or why the other party has attended, or the relationship between the two parties,” she said.

In confronting CCTV footage shared by Victoria Police, the men carried cricket bats and planks of wood. The incident is believed to have occurred between 9pm and 10pm.

Constable Hardie said up to six people were injured in the attack, including a 36-year-old Williams Landing man, a 28-year-old Tarneit man and a 35-year-old Tarneit man who were hospitalised with serious injuries.

“For something like this to happen, with six victims overall, for people that were just meant to be having a nice barbecue after work, it’s obviously of great concern for us,” she added.

While the warehouse where the brawl took place is leased by local business Tiger Trailers, police do not believe the “business itself is overly related with what’s happened”.

Anyone with information is encouraged to contact Crime Stoppers on 1800 333 000.