Six people are being quizzed by detectives over a shooting in Kettering that saw a man lose his leg.
The incident happened in Field Street at about 4.45pm on Saturday (October 14).
Police have now released CCTV footage of a van they believe is linked to the shooting.
Det Insp Emma Nealon of Northamptonshire Police said: “This was an extremely serious incident and we have a team of officers who are working to secure as much evidence as possible.
“We are especially keen to speak to any witnesses who may have seen a white Iveco van driving around the Kettering and Burton Latimer areas between Saturday and Sunday lunchtime.
“We believe the vehicle, registration YD52 NGM, is linked to the shooting.
“We are treating this as an isolated shooting and wish to reassure the public that incidents of this nature are extremely rare.”
Police are currently questioning five men, aged 32, 35, 38, 45 and 60 as well as a 28-year-old woman.
Anyone with information should call Northamptonshire Police on 101, quoting Operation Jubilee, or ring Crimestoppers, in confidence, on 0800 555111.