A Middle Eastern crime gang armed with guns and knives is behind a string of robberies at gaming venues across Melbourne's north and west, police say.

Officers said the syndicate, with members aged as young as 16, stormed eight businesses in recent months, threatening staff with weapons before making off with cash.

The Armed Crime Squad released footage of some of the robberies, showing the masked offenders punching patrons, smashing property, and jumping behind counters to empty registers.

Detective Inspector Stephen Clark said the gang had stolen more than $100,000.

"It appears at this stage that the armed robberies have been committed by the same Middle Eastern crime syndicate," Detective Clark said.

"On each occasion the offenders, who we believe are aged between 16 and 25 years, were armed with a firearm and an edged weapon, and threatened staff."

The robberies occurred at Laverton, Epping, Thomastown, Kealba, Fawkner and Moonee Ponds between June 2 and August 11.

Police charged two people aged 16 and 21 with armed robbery earlier this month.