ST. LOUIS (AP) — A potential aerial surveillance program aimed at helping St. Louis police investigate the city’s soaring violent crime problem has cleared one hurdle. The St. Louis Post-Dispatch reports that the Board of Aldermen voted 15-14 Friday to give preliminary approval to the measure. It would direct Mayor Lyda Krewson or her successor to contract with an Ohio-based company proposing to fly airplanes up to 18 hours a day over the city. The mayor hasn’t said if she will sign or veto the measure if aldermen pass it next week. Backers say the cameras could track the path of suspects and vehicles from key crime scenes. Opponents warned that the plan posed a threat to civil liberties.