A teenager threatened to stab an 18-year-old for refusing to hand over his iPod during an attempted robbery in Northampton.
At about 1pm on Wednesday, the 18-year-old was in Greatfield Court, Thorplands, when he was approached from behind by a teenage boy who asked him for the time.
The victim took out his iPod to read the time and the offender tried to grab it.
The offender then threatened to stab the victim, but as he could not see a knife he kept hold of it and struggled against him whilst he shouted for help.
The offender then punched the victim in the face, but he continued to hold onto the iPod and refused to let it go.
The victim eventually managed to break free and run away.
The offender is white and spoke with a local accent. He was 5ft 8in and aged 16 or 17. He wore black tracksuit bottoms with a white stripe down the legs and thin grey gloves.
Witnesses can call Northamptonshire Police on 101 or Crimestoppers on 0800 555111.