A 21-year-old former North Stonington man accused of sexually assaulting a young girl over a seven-year period made his first appearance Monday in the New London court where major crimes are heard.

Allan H. Smith, who is charged with second-degree sexual assault, third-degree sexual assault and risk of injury to a minor, was arrested by state police in June following a three-month investigation. The victim, a teen-ager, disclosed to a school psychologist in March that Smith had been sexually assaulting her for seven years, according to an arrest warrant affidavit prepared by state police detective Michael Hoagland. The psychologist notified the school principal and called state police.

Smith admitted to sexually assaulting the girl when confronted by police, according to the affidavit. He said he was “disgusted with himself and has made some serious mistakes.”

At his court appearance, defense attorney Michael A. Blanchard entered a not guilty plea on Smith’s behalf. Judge Susan B. Handy appointed attorney Priscilla F. Hammond as the victim’s guardian ad litem, reminded Smith he is to have no contact with her and continued the case to Aug. 19.

Smith is free on a $200,000 surety bond and is living in Ashford, according to court records.