The incident took place between 6am and 7am yesterday (Tuesday, March 5) where a 64-year-old man was targeted after withdrawing money from a cash machine at Sainsbury's in the city centre.
The victim had walked through Langdale Road, Bulk Road and Parliament Street to withdraw the money.
As he returned along the same route, he was attacked from behind by a man and pushed over near Riverview Close.
The attacker took the victim’s wallet before making off from the scene.
The victim man was not seriously injured, police said.
The man behind the robbery is described as tall and of slim build.
He was wearing a baseball cap, grey trousers and a dark green wax jacket.
Det Sgt Paul Richardson, of Lancaster CID, said: “An investigation is underway following a robbery in Lancaster.
“A man has withdrawn some cash before being pushed to the ground and robbed. Thankfully he was not seriously injured but the incident has understandably left him very shocked.
“At this stage we do not know if the victim was followed before the offence, but we are appealing for anybody who may have seen the offender described, or saw anyone acting suspiciously in the area between 6am and 7am, to come forward.
“The route is well used by morning commuters who might have seen what happened. We would also encourage any drivers with dashboard mounted camera footage which may have recorded the offender or offence to contact us.”
Anyone with information can call 101 or email [email protected] quoting log 0156 of March 5.
Alternatively independent charity Crimestoppers can be contacted anonymously on 0800 555111