Police are appealing for witnesses after a girl and boy were robbed on their mobile phones in Littlemore.

The incident happened shortly after 8pm on Monday in Champion Way, when a 14-year-old girl and her 15-year-old boyfriend were approached by a man with a knife who demanded they hand over their phones. They handed over their phones and the man cycled off along the road.

He is described as white, 5ft 7in tall, aged about 18, with a slim build. He was wearing a white Adidas hooded top with grey stripes on the sleeves and black tracksuit bottoms He was riding a white BMX bike with black trimmings and stunt pegs on the rear wheels.

Det Sgt Kevin Parsons said: “I would like to speak to anyone who was in the area at the time who may have seen this man, either before or after the incident.

“I would also like to hear from anyone who recognises the description of this man or the bike he was riding on.”

Anyone with information should contact Det Sgt Parson via the 24-hour Thames Valley Police Enquiry Line on 0845 8 505 505. Alternatively, you can contact the Crimestoppers charity anonymously on 0800 555 111.