GREELEY, Colo. (CBS4) – Dec. 20 marks the 34th anniversary of the disappearance of a 12-year-old girl in Greeley. Jonelle Matthews was last seen going into her home just after 8 p.m. on Dec. 20, 1984.

Police say they continue to investigate her disappearance, hoping new advances in technology will help as they re-interview witnesses in the case.

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Police still do not know what happened to Matthews after friends dropped her off at her home, 320 43rd Avenue Court, after singing in a Christmas concert at Franklin Middle School. She may have been home alone for a half hour before police believe she was kidnapped, but they never found any proof — not a chance sighting, never a suspect named, and her body has not turned up, baffling investigators for years.

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There is a reward. A team of new investigators does believe that someone knows what happened to Jonelle. Police say they are particularly interested in information concerning the choir activities the evening of the 20th, and hearing from individuals who might have interacted with Jonelle in the weeks and days before her disappearance.

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If you have any information, please contact us at (970)351-5100. A cash reward is available in this case even if you have been interviewed before. Whether you have been interviewed or not, now is the time to come forward. Our investigative team is dedicated to finding Jonelle and we believe we will find her, as she deserves nothing less.