LAS VEGAS (KLAS) — Las Vegas police report 15 sex offenders were arrested last week for not following sex offender registration laws, another three were arrested for outstanding warrants related to current sex crime investigations.

The verification operation is conducted periodically to make sure sex offenders have registered the correct address where they are living.

Sex offenders are required to check in with law enforcement based on what tier they have been assigned to. The most serious offenders are Tier 3 and must check in quarterly. Tier 2 must check in bi-annually and Tier 1 must check in annually. The rules regarding sex offender registration can be found at this link.

In this operation, which took place the week of June 7 – 11, more than 620 sex offenders were contacted throughout the Las Vegas valley. The operation was conducted by Metro’s Sex Offender Apprehension Team, U.S. Marshals Service Sex Offender Predator Apprehension Team and Pacific Southwest Regional Fugitive Task Force.

There is a website with a database that lists the locations of sex offenders registered in Clark County.