Western Adelaide police are investigating two attempted robberies that occurred within 30 minutes of each other yesterday.

In the first attempted robbery, at about 2.45pm a man armed with a knife entered the Red Deli on Victoria Road, Taperoo and demanded money. The store assistant refused and stated that she was going to call the police, and the man left empty-handed.

At about 3.10pm, the same man entered the Liberty Grove Deli on Liberty Grove, Woodville Gardens, and placed an empty shopping bag on the counter and again demanded money. Once again, the shop assistant refused and called police immediately. The man then left the store.

He is described as being of Caucasian appearance, about 175cm tall, slim build, and was wearing a dark-coloured West Coast Choppers jacket, sunglasses and grey shorts.

Police are making further enquiries in to whether this suspect was involved in the aggravated robbery of an Evandale restaurant last night at about 10pm.