DENVER -- Colorado's sex offender registry is touted as an easy way to check whether any predators live in your neighborhood. But in a spot test Thursday, 7NEWS found several addresses listed for sex offenders in Denver that were not current or accurate.

7NEWS checked 10 addresses in Denver, where the sex offenders were listed as wanted for "failure to register."

The address listed as Joseph Thomas Hatchett's last known location, 1702 Franklin St., is a vacant lot. Records show he is wanted on failure to register charges, and was convicted in 1995 of aggravated sexual assault of minor children.

At the home listed for registered sex offender Manuel Jose Roman Herrera -- 905 Hazel Court -- the house is vacant.

The people living at 1010 Tennyson St. said it's been four years since the registered sex offender listed lived there, but said police have repeatedly come to the home to try to find him there.

All the offenders checked are wanted for failure to register.

"Sex offenders are professional escape artists. We need the public's help to help find them," said Lance Clem with the Colorado Department of Public Safety. "I think local law enforcement do about a good a job as they can do with the resources they've got."

The state's sex offender management unit attempts to keep tabs on Colorado's nearly 11,000 registered sex offenders.

"Those who are under active supervision we have the ability to monitor much more closely," said Chris Lobanov-Rostovsky, who oversees the sex offender management unit with the Division of Criminal Justice.

Unlike other states, where sex offenders' high-profile crimes went unnoticed by parole officers, Colorado requires certain sex offenders take regular risk assessment and polygraph tests.

Colorado also gives special training to parole officers who work with sex offenders and assigns one parole officer for every 26 sex offenders, compared to one for 66 in the general population.

Local law enforcement supplement resources with regular multi-agency sex offender sweeps.

In October, officers in Colorado and Wyoming arrested 106 fugitive offenders and checked the addresses of more than 2,000.

Still, the problems uncovered with inaccurate addresses show tracking sex offenders is still a difficult and time-consuming task, and Colorado still has a lot of work to do.