Indiana University Student Lauren Spierer's Disappearance Still A Mystery

The disappearance of Indiana University sophomore Lauren Spierer two years ago still has investigators baffled.

The 20-year-old was reported missing on June 3, 2011, when she was heading to a party and reportedly vanished hours later.

According to Fox News, police are focusing their investigation on two theories: "Spierer was abducted by a stranger as she walked alone to her apartment, or she died inside the apartment building of three male acquaintances and her body later disposed of."

Mike Harkins, who retired from the FBI last year, has skepticism about both theories.

"Stranger abductions are not very common. They do happen and it could have happened in this instance, but overall they are rare," he told Fox News. "It's difficult to dispose of a body like that and then have that not be traced back to the individuals."

Parents of Lauren, Rob and Charlene Spierer reportedly believe their daughter may be dead and suspect the male acquaintances last seen with her have knowledge of what happened to her. Jay Rosenbaum, Mike Beth and Corey Rossman are the last known people to see Spierer alive, according to police.

Rossman, who according to Fox News claims he "remembers little of what happened that night, was seen on surveillance video and by witnesses accompanying a visibly incapacitated acquaintances as the two made their way from a popular bar to her apartment and then to his over the course of a few hours."

It's unclear if there were any drugs in Spierer's system that night.

The three males who last saw Spierer deny allegations that they were involved in her disappearance. Leads pointing to abduction have shown inconclusive. No arrests have been made and no body has been found.

The Spierers keep their daughter's memory alive through photos and cherish the memories they have of Lauren.

"One of my favorite memories was probably my last memory of Lauren she came home and surprised me for Mother's Day just before she disappeared," Charlene to Fox News. "I talked to Lauren every single day," she said." I can hear her voice - she's just such a loving girl."

Anyone with information on the case can call the Bloomington Police Department 24-hour tipline at 812-339-4477 or contact them by email at policetips@bloomington.in.gov.