A TEENAGE girl was threatened with a knife during a terrifying robbery in a High Wycombe alleyway this week.

The 17-year-old victim was walking in the alleyway next to Totteridge Mosque, which runs between Totteridge Road and Townfield Road, between 6.20pm and 6.30pm on Monday.

She was approached by a man who pointed what the victim describes as a kitchen knife at her before demanding her purse and iPhone and grabbing them.

The girl, who was uninjured, ran from the scene.

The suspect is white, of medium build, in his thirties, about 5ft 8in tall, with short light ginger frizzy hair, which was possibly balding and with light ginger stubble.

He was wearing a dark thigh-length padded coat and blue jeans.

The items stolen were a white iPhone 5 in a clear plastic case with a black giraffe motif on the reverse, and a black Ted Baker purse containing cash, bank cards and loyalty cards.

Investigating officer, PC Helen Gilbert said: “I would like to appeal to anyone who recognises the description of the offender, or has any information about the offence to contact police immediately via 101.

“This was a particularly frightening experience for the victim, and I am determined to bring the perpetrator to justice.”