Police Officer Shot During Traffic Stop

In Phoenix, a police officer was shot during a traffic stop.  The person that shot him (or shooter) are still on the loose, and left the police officer severely injured.  He was shot multiple times and was lucky to have been wearing his protective armor.  The officer had pulled over a car, and after he stepped out of his vehicle he was shot many times in the chest and it is said that he only survived because of his vest.  Investigators have no information linking to reasoning behind the shooting yet.