Police are appealing for witnesses after a robbery at Rockdale yesterday.

About 10am yesterday (Friday 25 November 2011), a 32-year-old woman was withdrawing cash from an automated teller machine on the Princes Highway when a man allegedly approached her from behind and shoved her, causing her to fall.

The man allegedly stole an amount of cash from the woman before fleeing.

A 35-year-old man who witnessed the incident chased and caught the alleged offender, forcing him to hand back the cash.

The alleged offender left the scene before police arrived.

Police would like to speak with a man who may assist with the investigation. The man is described as being Caucasian, approximately 40-years-old, 183cm tall, with a solid build.

He has sandy brown short hair and was last seen wearing black tracksuit pants and a green or blue-coloured jumper.