Chippewa Falls Police Investigator Robert Teuteberg has a message for parents -- keep a close eye on who your kids are talking to on the internet.
His department is investigating a sexual assault that it says happened last week.
According to the criminal complaint, it involved Nickolas Raether of Chippewa Falls and a 16-year-old girl he knew through Facebook.
It says Raether brought the girl and her friend to his Chippewa Falls home, spiked their drinks and sexually assaulted the 16-year-old.
When her friend tried to intervene, it says Raether pushed her away.
But this alleged incident may not be the only one.
"Through this investigation we came to find there were several other juveniles who we suspected had contact with someone using the screen name Nick or Nickolas Raether," said Chippewa Falls Police Department Investigator Robert Teuteberg.
Police believe Raether started conversations with dozens of girls online, mainly from Eau Claire and Chippewa counties, but possibly as far away as Madison and La Crosse.
"It seems there is a real brief conversation then it goes into talk of sexual activity and then there could be exchanging of photographs as well," Teuteberg said.
Police now want to know if there are other girls out there who got a message from Raether or even met him in person.
He says parents need to have an open conversation about social media with kids, adding they would likely be surprised about some of the topics that are being talked about online.
"Conversations about drug abuse, narcotics, alcohol, meeting up on safe locations," he said.
He says if you are unfamiliar with social networking talk with a friend or relative. Because knowing how it works he says can help prevent your kids from becoming a victim.