A would be robber was forced to smash his way out of a Brinsmead service station after a quick thinking employee locked him inside the store.

Around 9.20pm a 50-year-old male employee saw the man, who was armed with a knife, enter the Brinsmead Road petrol station. The employee fled to safety, locking the front doors as he left.

After failing to open the cash register the man attempted to flee via the glass front doors. However, when he realised they were locked, he pulled one of the doors towards him until it shattered.

The man jumped through the broken glass and attempted to escape however he was tackled by the employee with the pair struggling until the offender produced a knife, threatening the 50-year-old.

The offender was last seen running off in a southerly direction.

The employee was not physically injured and no property was stolen during the attempted robbery.

The man is described as Caucasian and approximately 175 to 183cms tall. He was wearing a blue, long sleeve hooded top with grey sleeves, blue cargo pants and had a cloth covering his face.

Police investigations are continuing.