HOUSTON -- Investigators need the public's help to find a convicted sex offender who has warrants out for his arrest in two states, KPRC Local 2 reports.

Houston police said Joseph George Vaquera, 27, is wanted on charges of violating sex offender registration requirements and probation violations.

Vaquera was sentenced to four years in prison in 1999 after a conviction for the aggravated sexual assault of a 13-year-old girl. After his release, Vaquera was required to annually register as a sex offender.

Investigators said Vaquera registered in Texas in 2002 and 2003 before moving to and registering in Wisconsin in 2004.

Wisconsin authorities said Vaquera was convicted on a charge of aggravated sexual assault in 2004 and received probation. Officials said he violated the terms of his probation and a warrant was issued for his arrest in 2005.

Houston police said Vaquera may be in the Houston area. In 2006, Child Protective Services officials said they discovered that he had moved in with a woman and several children at 1651 Witte Road in northwest Houston.

Investigators said Vaquera may have also recently stayed with his mother at her home in the 10100 block of Westview Drive.

Crime Stoppers offered a $5,000 reward for information leading to Vaquera's arrest. Anyone with information is asked to call 713-222-TIPS.