This menacing knife is identical to the one wielded by a masked robber who tried to hold up a York fish and chip shop.

Do you recognise it?

Detectives leading the investigation believe it could be key to tracing the raider.

The Sakana knife, which has a 9in blade, was later found near the scene. The incident happened at the Chips & Things fish and chip shop in Front Street, Acomb, last Wednesday at around midnight.

The shop owner, who lives above the takeaway, was returning to the shop after dropping off a member of staff when he saw a man crouching in the back yard.

The knifeman pounced and demanded money but the shocked shopkeeper hurled a box of computer gear he had been carrying at him before running off. He was pursued for a short distance before the attacker gave up the chase, walked back and picked up the box.

Detectives believe the raider had been after the day's takings, but he fled with the box containing about £700 worth of computer CD ROM's.

Det Con Duncan Thackray, of York CID, said the knife pictured was found near the scene and believed to be part of a set.

He said: "This knife is identical to the one the shop owner was threatened with. If we can trace its origins it would greatly assist the investigation."

The man police are hunting in connection with the robbery is described as white, 5ft 10in to 5ft 11in tall and of stocky build. He was wearing a balaclava, black padded jacket, jeans and boots.

If you can help, contact DC Thackray at Fulford Road police station on 01904 631321.

Updated: 10:26 Wednesday, January 24, 2001