Security guard foil attempted Melbourne jewellery store robbery

Four would-be thieves have fled after a security guard scared them away from a jewellery store in Brighton, in Melbourne’s south-east.

Police said a stolen Mercedes hatchback pulled up outside Holloway Diamonds on Church Street about 10.20am.

One of the four masked men used a sledgehammer in an attempt to smash the front of the shop open, police said.

Police scour the scene for evidence. (9NEWS)

They were last seen driving along Carpenter Street, towards North Road.

Witnesses told 9NEWS the daylight attempted robbery was “frightening.”

“I heard smashing and crashing…I’m a bit shaken,” hairdresser Henry Zelener said.

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