Minnesota Bureau of Criminal Apprehension

The charges in the case stem from a cyber tip originating with Snapchat.

The Minnesota Bureau of Criminal Apprehension issued the alert for 31-year-old Brian Spencer.

The charges include use of a minor in a sexual performance/pornographic work.

The investigation started when the staff and the Twin Cities library viewed to the manifesto.

He was accused of sexually assaulting the juvenile while keeping her hidden from authorities in a tent that he had set up behind a friend's home.

Police say they are not looking for any suspects.

A news release says the Minnesota Bureau of Criminal Apprehension is assisting with the investigation.

The Walker Police Department says the man was charging at an officer with a knife.

She was the subject of a statewide endangered missing person alert that was issued last month.

Family members say he is known to visit abandoned properties and tunnels.