A St. Louis police detective shot in the shoulder early Thursday was fired on as he followed his own vehicle, which he had loaned to a family member who didn't return it, police said.

Interim Police Chief Lawrence O'Toole said the officer, 54, was stable at St. Louis University Hospital. Police are looking for at least two suspects in the shooting.

Police said shortly after the shooting that the detective was investigating a stolen vehicle, and later confirmed that the car he was following about 1:20 a.m. Thursday belonged to him. He had let a relative borrow it several days earlier and the vehicle wasn't returned, police said. It was unclear if the vehicle was reported stolen to police.

The detective — in an department-owned but unmarked white Dodge pickup — began following the car when "at least two suspects emerged and fired shots at the officer, striking him in the shoulder," police told the St. Louis Post-Dispatch.