A manhunt was underway Sunday in Tennessee for the killer of a Memphis police officer who was fatally shot during a traffic stop on Saturday night, officials said.

Sean Bolton, 33, died from multiple gunshot wounds after being discovered critically wounded at about 9:15 p.m. local time Saturday, Memphis police said. A citizen used the officer's radio to report the shooting, police said.

Bolton had worked for the Memphis Police Department since October 2010. He is the third Memphis officer to be shot and killed in just over four years.

(Reporting by Carey Gillam in Kansas City; additional reporting by Curtis Skinner in San Francisco; editing by Digby Lidstone)