ST. LOUIS (AP) — Two St. Louis police officers are hospitalized after being shot in neighboring Ferguson.

One is in very critical condition. Police Chief John Hayden says the two officers were in a marked squad car together around 1 p.m. Wednesday when they spotted a car believed to have been involved in an overnight killing.

When the officers approached the car, the occupants opened fire. Hayden says it isn’t clear if the officers returned fire. One officer was struck in the leg. The other was struck in the abdomen.

Four people in the car were taken into custody.