ASPEN, Colo. (CBS4) – CBS4 has learned that authorities in Aspen have arrested the father of reality TV star Heidi Montag on an oustanding arrest warrant for sexual assault on a child and incest charges.

Authorities say the case does not involve Heidi Montag Pratt or her sister Holly.

Authorities in Aspen arrested William Montag, 67, on Thursday, on a failure to appear charge, according to jail records. It turns out Montag had been wanted on a felony warrant from Centennial, a Denver suburb, for sex assault on a child by a person in a position of trust. The sex assault warrant for Montag was issued this past Monday, according to Colorado court records.

Court records also indicate the alleged incidents in question involving William Montag took place between July 1, 1996, and June 30, 1998.

The court records also say the case involves incest.

Arapahoe County Sheriff’s Captain Larry Etheridge told CBS4 while the victim was not Heidi Montag or her sister Holly, there was a single victim who was between the ages of 14 and 17 when the alleged assaults occurred.

Heidi Montag Pratt became famous for her role on the reality TV show “The Hills.” She and her husband Spencer Pratt went on to appear in other reality TV shows like “I’m A Celebrity … Get Me Out of Here!” Montag also received notoriety when she admitted undergoing 10 plastic surgery procedures in one day.

Aspen Police Department spokesperson Blair Weyer told CBS4 William Montag had been most recently working in the ski industry and was arrested Thursday at his place of employment.

Attempts to reach William Montag’s wife and other family members were not successful. TMZ.com reports that their sources say Heidi Montag and her husband Spencer Pratt are familiar with William Montag’s accuser and say she has stalked them over the years and “is determined to destroy the family.”

No bond has been set for Montag’s to be released from jail.

CBS4 Investigator Brian Maass has been with the station more than 30 years uncovering waste, fraud and corruption. Follow him on Twitter @Briancbs4.