The Department of Public Safety released more information to ABC15 on Wednesday after a gun was found along Interstate 10.
DPS said a 9mm Kahr handgun was found on Interstate 10 and 59th Avenue on December 17. A contractor with the Arizona Department of Transportation found the gun while picking up trash.
According to DPS, the gun was not reported stolen and no one has reported the gun missing.
The handgun has been submitted to the crime lab for examination and to compare to any other known shootings in the area.
DPS said the gun is not related to any freeway shooting investigation.