A woman has told police she had a fake gun pointed at her in an alleged attempted car jacking

Police are appealing for information after a woman was threatened with an imitation firearm in an attempt to steal her car in Castlemaine.

Detectives were told a man approached the woman armed with an imitation firearm at a Railway Avenue car park on May 30 around 6am. 

The man allegedly threatened her and demanded the keys to her Audi as she was getting out of the car. 

The woman refused and on each occasion she heard the click of the gun as he pulled the trigger. 

The woman escaped uninjured. 

The offender fled the scene in the passenger seat of a white Holden Commodore.

The car was last seen heading east along the Pyrenees Highway heading towards Chewton. 

He is described as Caucasian in appearance, aged in his 20s, about 168cm tall with a stocky build, fair wavy hair and clean shaven. 

He was wearing a light coloured long sleeve top and light coloured baggy track pants. 

The driver is described as being similar in age but thinner than the armed man and has brown coloured hair.