A manhunt has been launched for an axe-wielding crook in a motorbike helmet who robbed a Melbourne convenience store.

Police are searching for a motorcycle helmet-wearing man who robbed a Footscray convenience store while armed with an axe.

The alleged theft took place on Sunday, December 12 after onlookers reported seeing a man riding a bicycle past a store on Tiernan Street near Ballarat Road about 7.15pm.

He then approached the counter in the store armed with an axe and demanded cash from the register which the female staff member complied with.

The man eventually rode off, weaving in and out of traffic on Ballarat Road, before travelling north on Hoadley Court.

He is described as having a distinctive walk and was wearing a black Titanium jacket, dark-coloured track pants, black THH motorcycle helmet, surgical face mask and had yellow runners down the back of his pants.

The bike he was riding was silver with different wheels on the front and the back.

Police have released CCTV and images of a male they believe can assist them with their inquiries.

Anyone with information is urged to contact Crime Stoppers on 1800 333 000 or at www.crimestoppersvic.com.au.

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