Police say a St. Louis County police officer was killed and a suspect was critically injured in an exchange of gunfire.

The Associated Press reports that police did not immediately identify the 33-year old officer, who was fatally wounded during the early morning shooting, Thursday, in Green Park, a small community in South St. Louis County.

A police spokesman, Benjamin Granda, says the suspect is undergoing "life-saving treatment," after being wounded by another officer.

Granda says that almost as soon as officers responded to a disturbance call, just after 5:00am, the suspect began shooting, striking the officer. A second officer then returned fire, injuring the suspect.

The suspect's name has not been released at this time.

Police say its the first on-duty death of a St. Louis County officer since October 2000.

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