St. Louis police say three people have been shot at a city park, one by a park ranger.

Police Chief Sam Dotson says the incident began Sunday evening when two men attending a barbecue at Carondelet Park started arguing.

Dotson said at a news conference that one of the men, a 38-year-old convicted felon, shot the other in the stomach. The victim was in critical, unstable condition.

The chief says the suspect fled in a car but a uniformed park ranger stopped the vehicle. He says the suspect got out and fired at least one shot, striking the ranger's vehicle.

The park ranger returned fire, striking the suspect. Dotson says a woman nearby sustained a graze wound during the exchange of gunfire. She was expected to be treated and released.

The suspect was in critical but stable condition.