A 60-year-old Grafton man has been charged with first-degree sexual assault after a 17-year-old girl went to the police station to report the man assaulted her while threatening her with a knife in his home.

Jimmie Oliver was charged Wednesday in Ozaukee County Circuit Court with first-degree sexual assault, second-degree recklessly endangering safety, possession with intent to deliver marijuana, possession with intent to deliver cocaine and maintaining a drug trafficking place, all felonies. 

He is being held in the Ozaukee County Jail on $100,000 cash bond. 

According to the criminal complaint: 

The victim met Oliver through a friend and had been purchasing drugs from him since she was 16. She said Oliver would take money for drugs, but "he would prefer to exchange them for sexual favors." She told police she didn't have a choice because she knew he had a gun and had threatened her.

She went to Oliver's residence July 17 to purchase drugs. Oliver asked her to perform a sex act. When she said no, he grabbed a knife, held it to her neck and then raped her, the complaint said. 

The girl was taken to Aurora Medical Center Washington County, where a sexual assault exam was completed. 

The next day, she returned to Oliver's residence to obtain evidence for police. At the home, she took two photos of Oliver. The photos show a man sitting on a couch without clothes.

The girl reported that Oliver sells drugs only to young girls, the complaint said.

Police executed a search warrant at Oliver's residence on July 18 and found a nylon lunch box filled with what police believed to be marijuana. They also found a handgun with additional magazine and ammunition, and wrapped baggies of white powder, which police believe to be cocaine. 

If convicted of all charges, Oliver could face more than 80 years in prison. 

Oliver is scheduled to be in court Aug. 8 for a status hearing. 

Based on the investigation, Grafton police believe there may be additional victims. They are asked to call Detective Dustin Cline at 262-375-5320 ext. 819 or Detective Justin Gehm at 262-375-5320 ext. 815. 

Contact Alex Groth at agroth@gannett.com. Follow her on Twitter at @grothalexandria.