A 16-year-old boy punched an armed man who tried to rob him in Kettering.
The victim was walking home and in Wallis Road when the incident took place between 9.30pm and 10.15pm on Wednesday, August 28.
Two men in a silver Jaguar XJ stopped him and one got out of the car with a knife in his hand.
He tried to grab the victim's phone but was punched in the face.
The teenage boy then ran off.
No description of the attackers was available from police.
Witnesses or anyone with information should contact police on 101.