When Newman tried to detain Keller, the driver pulled a gun and began shooting. Newman was struck in the neck, but he was able to return fire as he fell to the ground and Keller fled.
The other officer began treating Newman at the scene as other officers responded. Newman was airlifted to a trauma center, and he remains in critical condition.
Keller led police on a chase before crashing on the interstate. Following the crash, Keller was fatally shot by police, and a handgun was recovered from the scene.
The shooting is under investigation.
According to Chief Danny Baker, Newman was a veteran, and he had been with the department for over a year. Baker said he was proud of the work Newman had done with the agency and the bravery he displayed.
"Officer Kyle Newman is fighting for his life today because he responded to protect this community and was confronted with an armed individual who chose violence," Baker said during a news conference.
"We're hopeful that he is improving, but he's still very much in danger," he added.