The Winona County Sheriff's Department is investigating a sexual assault that was reported Sunday evening. 

The Winona County Attorney's Office is determining possible felony charges against 26 year old Bradley Brevig, whode mailing address is in Houston County but lives in Winona County.

Sheriff Dave Brand said Brevig was held in custody on suspicion of sexually assaulting a 17 year old girl.
                       
Brand said the alleged assault occurred at a residence along Stenson Ridge, near the Houston County line.  The sheriff's department was notified by Gunderson Lutheran Hospital in La Crosse after the alleged victim went there for treatment.
                      
Brand said the victim told authorities she was sleeping at the time of the alleged assault.