JACKSONVILLE, Ill. (CAPITOL CITY NOW) – A Jacksonville man is in jail after a month-long investigation into him allegedly sexully assaulting a minor.

Jacksonville Police say Austin D. Sims, 26, is being charged with Aggravative Criminal Sexual Assault.

According to a news release, an investigation began in August, and the assault involved someone between the ages of 13 and 16 who was known to Sims at an earlier date.

Sims has not yet made a first appearance in court, according to online court records .  Charges were formally filed Thursday, as was a request by prosecutors to deny pre-trial release.

Police say if you know anything about Sims and the victim, to call the Jacksonville Police Investigative Division at (217) 479-4636.