There are 15 offenders listed on the Franklin County Sheriff's website as non-compliant.
But a special operation this week called Operation Verify uncovered dozens more.
All over Franklin County this week, 800 homes got a surprise visit from the sheriff's office. They have been going door-to-door to track sex offenders to make sure they still live in the area and haven’t evaded authorities.
Out of those visits - 101 people could face criminal charges.
10TV was there as authorities faced the daunting task of tracking them down.
“I'm looking for Henry Martinez,” says Detective John Andrews after knocking on a door. A person answering the door says Martinez has moved to Oklahoma.
Detectives say Martinez is now a wanted sex offender for failing to let authorities know he moved.
“They're allowed to move out of state, but they have to let us know they're leaving the state so we can let Oklahoma know, ‘hey, this sex offender is moving into your area.’”
Det. Andrews says out of the 45 sex offenders he checked on Tuesday, he made contact with about 15.
Some offenders are easy to track and answer the door when Det. Andrews comes knocking.
But others weren’t so easy; like Gloria Sansone, who Andrews has learned no longer lives on Linwood Avenue in South Columbus.
Just a few doors down, Daniel Ingles - a sex offender convicted of rape - also appeared to be missing.
“How long you been here - since January?” Andrews says after speaking with someone at Ingles alleged residence. “Daniel’s been out since then, obviously,” concludes Andrews.
He says if they get no answer at the door, they'll leave notices. They ask sex offenders to bring in a utility bill or a driver's license with their address. “We try to be proactive to make sure sex offenders are where they say they are so the community is better informed that way.”
Andrews says that's why every door knock is critical. He wants to make sure the community is not only better informed, but safe.
If you want to be notified when a sex offender moves into your neighborhood, go to 10TV's CrimeTracker 10