ST. ALBERT, Alta. -- An Edmonton-area man is facing charges for the alleged sexual assault of his two school-age children, while the children's mother is accused of failing to contact police about it.

The Internet Child Exploitation unit in Edmonton began investigating in March after a referral from the National Center for Missing and Exploited Children in Virginia about a social media user uploading child pornography.

A suspect was identified and police seized a number of computer and electronic devices from a home in St. Albert.

Investigators discovered the alleged abuse, which they believe occurred over a period of at least three years.

The 35-year-old father is facing several counts that include sexual assault, while the 32-year-old mother is charged with causing a youth to need intervention under Alberta's Child, Youth and Family Enhancement Act.

The parents were charged on Tuesday but police have not released their names in order to protect the identity of the children.