Police have arrested a man over a bizarre milk bar robbery in Melbourne that was caught on the store's CCTV.

Security vision shows two bumbling bandits enter the store at West Footscray before they steal the entire cash register.

The attendant locked herself in a back room as one of the thieves helped the other fix up his ski mask.

View photos One robber needed some help with his balaclava. Source: Victoria Police More

View photos The unmasked man offered to help. Source: Victoria Police More

The other man was not covering his face.

The masked man jumps the counter and grabs the cash register before tossing it to his accomplice.

View photos He was given a hand before jumping over the counter. Source: Victoria Police More

View photos One of the men was not masked during the robbery. Source: Victoria Police More

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