Of the 4,500 registered sex offenders on New Jersey's public database, nearly two dozen are actively wanted by the police.

The offenders in the gallery below were listed as "wanted" or "active absconders" by the State Police registry.

Registered sex offenders are required to check in with authorities annually or every 90 days, depending on the offenses. They also must notify law enforcement when they move.

The public database traces back to the murder of a Mercer County girl in 1994. After 7-year-old Megan Kanka was raped and killed by her Hamilton neighbor, serial sex offender Jesse Timmendequas, her parents lobbied for a law that would notify the community when sex offenders moved in. Megan's Law was enacted in New Jersey that year and became federal law in 1996 after it was sponsored by New Jersey Congressman Dick Zimmer.

There are more registered sex offenders in New Jersey, but the public database only shows those in the moderate Tier 2 or severe Tier 3 risk categories.

Have you seen these sex offenders?

Earlier this month, New Jersey 101.5 spoke with law enforcement and child experts about the dangers of online predators.

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