Investigators did not find any weapons from the cars and had not confirmed if there were other occupants in the SUV or car.

"I think it’d be better to wait and see what our investigation shows," Leyshock said. "They may be related, maybe they’re not.”

Police believe the men were in their late 20s to early 30s.

Officers responding to the shooting on Plover first found the man in the car in the 4900 block, Leyshock said. They soon after found the SUV on fire on I-70.

After the SUV crashed, residents nearby ran to the vehicle to try to help the occupants and pulled the two men fatally shot from inside, Leyshock said. The neighborhood, which Leyshock used to patrol earlier in his career, is tight-knit, he said.

“I’m not surprised neighbors would run out there and risk their lives to try to save their lives. I think it’s pretty awesome,” he said.

Investigators were looking through the area with canines and attempting to interview witnesses after the shooting. Leyshock asked anyone with information to call to contact St. Louis Police or CrimeStoppers online or at 1-866-371-8477. Tipsters can remain anonymous and may be eligible for a reward.