Melbourne Embona Task Force detectives are investigating an armed robbery which occurred at a convenience store in Melbourne on Friday night.

Police have been told that a man entered the Elizabeth Street store around 4.50am.

The man picked up a pair of scissors, threatened the attendant and demanded that he hand over cash and cigarettes.

The attendant handed over a packet of cigarettes and nothing else.

The offender then reached over the counter and attempted to open the till but was unsuccessful.

He then left the store and was last seen running along Elizabeth Street.

Investigators have been told that the offender is perceived to be Caucasian, 30-40 years-old and with short brown hair.

At the time of the offence, he was wearing a blue hooded top with white squares.

Police have released still images and CCTV footage of a man that they believe may be able to assist with their enquires.