Police are investigating a series of armed robberies over the past month in Melbourne’s north eastern suburbs believed to be carried out by the same man.

On all four occasions, the man has entered the stores carrying a green enviro shopping bag, demanded money and fled the store with cash.

Investigators have been told a man entered an entertainment store in Main Road, Eltham on Monday 13 June about 8pm wearing a light green hooded top with the hood pulled around his face, a scarf wrapped around his face and gloves.

On Thursday 23 June about 8.15pm the same man is believed to have attended a bottle-shop in Plenty Road, Bundoora wearing a blue top and track pants.

It’s believed he then attended a supermarket in Plenty Road, Bundoora on Friday 30 June about 10.40pm. wearing a white hooded top and dark pants.

On Friday 8 July about 6.30pm, he entered a supermarket in Bell Street, Heidelberg West wearing a grey hooded top and sunglasses and carrying a towel over his arm as if hiding something

Whittlesea Crime Investigation Unit detectives have released an image of a man they believe may be able to assist them with their investigation.

Police have also released two images of the man captured on CCTV.

Police are appealing to anyone with information about the armed robberies to contact Crime Stoppers on 1800 333 000 or visit www.crimestoppers.com.au.