A 16-year-old boy was the victim of an attempted robbery in Peterborough city centre.
At about 5.10pm on October 22 the boy was approached by a group of three men. One of them threatened him, demanded money and attempted to steal his mobile phone.
The offender is described as being aged between 16 and 20, about 5ft 9in tall with short straight black hair. He spoke with a foreign accent and was wearing a dark grey coat with hood.
Police are particularly interested to trace the driver of a dark coloured Mercedes Sprinter van who stopped to assist the victim.
Anyone with information regarding this incident should contact police on 101, call Crimestoppers, anonymously, on 0800 555 111.