MIDDLE TOWNSHIP, N.J. (AP) — Authorities are hoping a new reward will help investigators find a southern New Jersey boy who disappeared in 1991.

Eleven-year-old Mark Himebaugh was last seen leaving his family’s Cape May County home to watch firefighters battle a marsh fire on Nov. 25, 1991. The only trace of him was a sneaker found on a Delaware Bay beach near his Middle Township home.

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An anonymous donor is offering $10,000 for credible information about Himebaugh’s disappearance and $25,000 for his safe return.

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Himebaugh’s mother, Maureen, has kept the same phone number for 20 years in hopes her now adult son will call.

She tells The Press of Atlantic City she hopes the reward will bring closure to her son’s case.

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