The victim, a 44-year-old man from Pakistan who had only had the shop two weeks, was forced to place hundreds of pounds of notes on the counter which were then stolen.

Detectives have released the dramatic footage in a bid to hunt for the "highly dangerous" man who still has not been caught.

The white robber, dressed in some kind of head covering, burst into the Mini Mart in Avenham Lane at 4.10pm on August 10 and demanded cash from the till.

The man, whose face was concealed, pulled the 12-inch blade from his tracksuit bottoms and pointed it at the shopkeeper's face.

One customer who had spotted the man stood outside witnessed the incident.

The man was in his late 20s, 6ft, slim, with short scruffy brown hair.

He was wearing dark hooded top, and a white cotton scarf with triangular black patterns. Police are studying CCTV.

Det Sgt John Crichton of Preston CID said: "The offender had his face covered and appeared ready to use the 'Samurai sword'.

"This man is highly dangerous and the police would ask the public to study the film, particularly the man's distinctive belt. If they know this offender please get in touch.

"The blade was a good 12 to 15 inches long.

"The victim does not come from Preston and has bought the shop recently. He is now going to enhance his security systems."

Anyone with information can call police on 01772 203203.

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