Underwater Search Turns up No Sign of Ariz. Police in Tucson, Ariz., say underwater searches have turned up no sign of a 6-year-old girl who disappeared from her home a week ago. Lt. Fabian Pacheco said Friday that investigators working on Isabel Mercedes Celis' disappearance spent the night combing through the lake at a local park with sonar equipment. He says they were acting on a tip, but he wouldn't elaborate. Officers also searched bodies of water in other city parks. Pacheco says police are also looking for anyone who took video during a baseball game that Isabel's family attended the night before she disappeared. Isabel's parents say they last saw the first-grader in her bedroom April 20, and they awoke the next morning to find her missing.