Police are seeking witnesses and anyone with information about an attempted abduction.
The incident happened in Roade on Friday night.
Between 8pm and 8.30pm, an 11-year-old boy was walking along High Street near the Cook pub.
A white transit van was parked at the side of the road and, as the boy walked past, a man stuck his arm out of the man and blocked his path.
The man told the boy to get into the van, but the youngster punched him in the face, knocking him to the ground, and ran away.
Det Insp Nick Purdie said: “This is a worrying incident but I would stress that it is the only one we have had.
“I am appealing for any witnesses to this incident or information in relation to any suspicious white van in the Roade area on Friday.
“If you recognise this man then please get in touch with us as a matter of urgency.”
The man is described as white, about 50-years-old and of average height and medium build.
He had a bald head and big, wide eyes, as depicted by an artist’s impression released by Northamptonshire Police.
According to the victim, the van was possibly a Ford Transit and drove off in the direction of Northampton Road and Hartwell Road.
Witnesses to the incident, or anyone with information, should call Northamptonshire Police on 101.
Alternatively, information can be given anonymously to Crimestoppers on 0800 555 111.