The car used by the gunmen accused of the attempted murder of Detective Chief Inspector John Caldwell was bought in Ballyclare.
Dissident republican group the New IRA admitted it shot the top PSNI officer in Omagh last Wednesday.
The blue Ford Fiesta, registration MGZ 6242, was bought in Ballyclare on Wednesday, February 8.
It was later seen heading along the M2 towards Belfast that night. It was fitted with false registration plates, FRZ 8414.
Detective Chief Inspector John Caldwell remains in a critical but stable condition in hospital after being shot in Omagh.
Detective Chief Superintendent Eamonn Corrigan said: “At this time we believe at least 10 shots were fired by the gunmen in front of terrified children and parents. That shows the completely reckless nature of this attack and the callous disregard the gunmen had for children and adults who were present at the time of the shooting.
“The gunmen fired from close range in the busy sports training area, which could have quite easily seriously injured or killed anyone close by. John’s own son was with him at the time and witnessed the shooting.”
Six men aged between 22 and 71, arrested as part of the investigation, remain in custody.
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