Tucson police secured a landfill near the missing 6-year-old's home… (Benjie Sanders / Arizona…)
The search for a missing 6-year-old girl continued in Tucson on Tuesday as authorities canvassed her neighborhood again and began a search in a city landfill.
Isabel Mercedes Celis was reported missing Saturday when her family went into her bedroom to wake her up around 8 a.m., officials said.
Police were called at 8:14 a.m. and were not able to determine whether the girl was kidnapped or if she had wandered off on her own, they said.
Within minutes, a widespread search began involving the U.S. marshals and the FBI.
A dislodged window screen turned up during the weekend investigation, though authorities would not disclose what window it came from.
Tucson police secured a landfill near the Celis' home and began sifting through the garbage Monday, Sgt. Maria Hawke told the Los Angeles Times in a telephone interview.
"We're not looking specifically for her body but for potential items of evidence that will provide clues as to what happened to her," Hawke said.
The Celis family, which includes Isabel's parents and two older brothers, will be allowed to return to their home Tuesday afternoon after being asked to vacate over the course of the investigation, officials said.
Due to the nature of the disappearance, police asked for "all hands on deck" and called in more than 75 officers, including canine and air units, Hawke said.
Authorities have interviewed all of the 17 registered sex offenders within a three-mile radius of the Celis home, the Arizona Daily Star reported.
The Arizona Department of Corrections brought in its bloodhounds and the U.S. Border Patrol has joined the search.
Isabel is described as just under 4 feet tall and weighing 44 pounds, with brown hair and hazel eyes.
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