Babylon Township officials keep track of sex offenders with new mapping technology, but it's possible some felons still slip between the cracks.

As per state law, high-risk convicted sex offenders must keep up to date information on their legal residence with the New York State Sex Offender Registry. Babylon uses the information along with its mapping system to determine whether each person lives the required quarter-mile away from schools, parks and day care centers.

The maps show town officials that two sex offenders live in violation of the statute. When News 12 Long Island's Bill Mooney went to those locations, though, he discovered one had moved away without re-registering and one was back in jail. Town officials admit because the system relies on the state registry, there could be some discrepancies.