A shop assistant was hit on the head by a masked man who snatched £200 cash from the till of a shop in Norbury on last Thursday night.

At about 9.20pm the man ran into the Spar at Bigginwood Cottages, St Oswalds Road, and threatened the 21-year-old man who was working on his own in the shop.

The man was hit on the side of the head police say possibly with a hammer before his attacker grabbed the cash and made off down St Oswalds Road.

Police say he was about 23, black, and wearing a black mask or balaclava.

Call PC Gary Davison of South Norwood Robbery Squad on 020 8768 1212, or anonymously call Crimestoppers on 0800 555 111, with information.