PD: Parents of Isabel Celis took polygraph test

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Sergio and Becky Celis Sergio and Becky Celis

The parents of Isabel Celis took a polygraph test early in the investigation of the missing 6-year-old girl, Tucson police said Thursday.

The results of Sergio and Becky Celis' tests will not be shared, Sgt. Maria Hawke of the Tucson Police Department said at a news briefing.

Hawke said investigators have not given up hope that Isabel is alive and with someone. 

Isabel's parents said they last saw her in her bedroom the night of April 20 and discovered she was missing the next morning. Police said a window was open with the screen pushed aside.

Hawke spoke on day 13 of the investigation and said law enforcement has received about 500 tips.

Friends of the family said they have passed out more than 20,000 flyers. (Click here for a printable flyer).

Isabel is described as just under 4' tall and weighs 44 pounds, with brown hair and hazel eyes.

Anyone with information about the whereabouts of the girl is asked to call 911 or 88-CRIME.

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