The charity Crimestoppers is offering a reward of up to £10,000 for information after a 16-year-old boy from Northampton was shot.
They also want the firearm used in the shooting to be recovered.
The teenager was found injured in Booth Meadow Court in the Thorplands area just after 7.30pm on Monday 30 September.
He suffered serious but not life-threatening injuries.
CCTV footage released by Northamptonshire Police shows two boys seen in the vicinity of the incident.
Lydia Patsalides, East Midlands Regional Manager for Crimestoppers charity, said: “Our charity believes everyone has the right to be safe."