A former Casper resident has been charged with the sexual abuse of a girl that occurred more than four years ago, according to court records.

Carroll Michael Chiasson, 24, heard the charges of two counts of first degree sexual assault and one count of second degree sexual assault during his initial appearance in Natrona County Circuit Court on Monday.

The first-degree sexual abuse charges each carry penalties of up to 50 years imprisonment. The second-degree sexual abuse charge carries a penalty of up to 20 years imprisonment, according to the criminal warrant read by Circuit Court Judge Michael Patchen.

Because Chaisson now lives in Fargo, N.D., and has virtually no ties to the Casper community, Patchen set his bond at $75,000. He will have a preliminary hearing in a few weeks to determine whether his case should be bound over to district court for trial.

The case began locally last month when Natrona County Sheriff's investigator Aaron Shatto reviewed a report of a girl who had been interviewed by a detective from a city outside Wyoming, according to Shatto's affidavit filed in Natrona County Circuit Court.

The girl, who had been Chaisson's step-sister when the two lived in the same household in Casper, told the detective she was six or seven when the abuse began and ended when she was 11 or 12, according to the affidavit.

The most recent alleged abuse occurred in December 2010, when Chaisson was a student at Casper College. Chaisson's mother had kicked him out of her house that summer, and he lived with the girl's aunt and uncle until January or February 2011, according to the affidavit.

In September 2014, the detective posed as the girl, chatted with Chaisson on a social media site, and discussed the alleged abuse, according to a fax of the conversation reviewed by Shatto.

Chaisson responded that he still fantasized about the encounters, but asked the detective, posing as the girl, to delete the conversation, according to the affidavit.