Questions, rumors and fears spread through a Kirkwood neighborhood today after a police sergeant was shot and killed by a gunman. Authorities continued their search today for a suspect identified by police as Kevin Johnson, also known as Kevin Tatum, 19, whose last known address was in the 400 block of Saratoga Street in Kirkwood. A white Ford Explorer that police believe was used by Johnson Tuesday night was found today in Ferguson. Other sightings of Johnson throughout St. Louis County were also reported.