Monday marks 28 years since Mark Himebaugh disappeared.

On November 25, 1991, 11-year-old Mark Himebaugh was walking toward a playground in Del Haven, and he hasn't been seen since.

According to Middle Township Police, a park guard was the last person to see him at about 4 p.m. that day.

The Middle Township Police Department, Cape May County Prosecutor's Office and the Federal Bureau of Investigation continue to investigate this case.

Mark Himebaugh - Photo: MTPD

Since Himebaugh’s disappearance, the National Center for Missing and Exploited Children has generated several age-progression photos. The photo above is what he may look like now, in his mid-30s.

Himebaugh’s mother, Maureen, said on that day she told her son she was dropping off a neighbor to pick up their car at a repair shop in Middle Township. But he didn't want to go along because a fire had broken out in town and he wanted to watch what was happening nearby. When she returned from the errand, her son had vanished. A convicted child sex offender who remains behind bars, Thomas Butcavage, has been described by police as a person of interest in the case. But he denies involvement and the case remains officially unsolved.

Anyone with Information regarding the disappearance of Mark Himebaugh can contact the Middle Township Police Department at 609-465-8700 or the National Center for Missing and Exploited Children at 800-843-5678.

With prior reporting from David Matthau.