A man already serving a life prison sentence for the 2014 death of a Tucson teenager is facing a retrial in the kidnapping and killing of a 6-year-old girl.

Jury selection began Tuesday in the second murder trial for Christopher Clements in the Isabel Celis case.

Celis vanished from her parents’ Tucson home in April 2012.

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Authorities said Clements became a suspect in 2017 when he told the FBI he could lead investigators to Celis’ remains in return for having unrelated charges dropped.

At the time, Clements said he simply knew the location of the girl’s remains but had nothing to do with her death.

After a 10-day trial last year, Pima County Superior Court jurors deliberated for nine hours over two days but couldn’t reach a verdict on the first-degree murder charge against Clements. A mistrial was declared last March.

Four weeks have been set aside for the retrial.

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Clements, 42, was sentenced to natural life in prison in November 2022 for the kidnapping and killing of 13-year-old Maribel Gonzales, who disappeared in June 2014 while walking to a friend’s house.

Her body was found days later in a remote desert area north of Tucson.

A different jury heard Clements’ first trial involving Celis.

Authorities said the Gonzales case included evidence that her body showed a partial DNA match to Clements, but Celis’ remains were so degraded that the first trial didn’t include any claim of a match to the defendant.

Clements, a convicted sex offender with a long criminal record, was arrested in 2018 and indicted on 22 felony counts in connection with the deaths of the two girls.