JANESVILLE, Wis. -

Rock County investigators are still waiting for lab results to determine exactly how Aprina Paul died. The Fitchburg woman’s remains were found, nearly two weeks ago, in a burn pit near Evansville.

Investigators said like most young adults, the 18-year-old had a significant presence online, and her digital footprints led them to the home of Nathan Middleton.

"When you go into an investigation, you have to have your eyes wide open to all possibilities," Lt. Todd Stetzer, with the Fitchburg Police Department, said.

When Fitchburg police began looking for Paul, their search for clues began by looking at her past.

"There was some indication she may have been involved in prostitution in the past, but when you’re talking to people, you get a lot of information," Stetzer said.

Police said they don't know whether or not Paul was working as a prostitute when she met Nathan Middleton. He told police they met after Paul responded to a Craigslist ad to party. About a week later, Paul's remains were discovered on Middleton's property.

Now, Middleton is facing charges, including hiding and mutilating a corpse and pandering.

Investigators said online records and texts connected Middleton to Paul.

"We had some indication she was meeting people online through different social networks," Stetzer said.

Kristen Uttech, a social media professor with Madison College, said social networking can lead to crimes. She advises anyone online to keep their guard up and trust their instincts.

"We feel like we know someone, we've read their profile, we've seen their interactions with other peers online, and the reality is we don't ever know who's on the other end of the computer until we meet them," Uttech said. "Know where you're going. Tell people where you're going, bring a friend, bring your cellphone and just use caution, use your gut."

Uttech said the average teenager has 350 friends on Facebook, many of whom they have never met. She suggested using the privacy settings to hide information from people you haven't met in person.

There has not been any update on when Middleton is expected to be in court to face those charges.