YUCCA VALLEY, Calif. -

 A school custodian who sexually abused a child over a period of several years and shared visual images of the molestations online pleaded guilty Monday to federal child pornography charges, according to a release from Thom Mrozek with the U.S. Attorney's office of Los Angeles. 

 Matthew Frazer, 39, of Yucca Valley, pleaded guilty to one count of distribution of child pornography and one count of possession of child pornography.

  Mrozek said in the release Frazer, who has been in custody since his arrest earlier this year, is scheduled to be sentenced on October 6.

  Prior to his arrest on January 31, Frazer was employed as a custodian with the Morongo Unified School District. The victim did not attend the schools where Frazer worked.

 The investigation into Frazer was initiated last year after the National Center for Missing and Exploited Children provided to the FBI a series of pornographic images depicting a young female being abused by a man. For several months, investigators attempted to identify the adult male in the images, and the FBI identified Frazier as the suspect earlier this year.

In a plea agreement, Frazer plead guilty to two felony charges in which he admits filming sexual explicit images of the young female victim from 2008 through 2012. He admitted to making a video in October 2009, when the victim was 6 years old, and again the following year when she was 7, according to court documents.

Frazer faces a mandatory minimum sentence of five years for the distribution charge and a maximum sentence of 30 years in prison as a result of his guilty pleas to both counts.

The plea agreement calls for the judge to impose a sentence of at least 10 years and up to 23 years, which will be followed by 10 years of supervised release.

This case is the result of an investigation by the FBI. The following agencies provided assistance during the investigation: the Riverside Police Department; the Riverside County Sheriff's Department; the San Bernardino Police Department; the San Bernardino County Sheriff's Department; and the San Bernardino County Probation Department.