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Lauren Spierer, a vivacious 20-year-old with a flair for fashion, should be clad in cap and gown next month celebrating her college graduation with classmates at Indiana University. Instead, Spierer's parents are left agonizing over her whereabouts after the young woman disappeared in 2011 without a trace from the streets of downtown Bloomington.

For two years, the family has been tormented by false leads, dashed hopes and what they say is an unwillingness to help from people who were last seen with their daughter. The recent discovery of still-unidentified human remains in a remote area of Indiana became the latest reminder of their continuing anguish.

"We’re experiencing a terrible strain," Spierer's father, Robert, told FoxNews.com. "We miss Lauren terribly and the not knowing makes it all the worse for us. We think about her every day and we talk about her every day. It’s not any easier today than it was two years ago.

"It’s hard for us with all of Lauren’s classmates graduating in May," he said. "It’s emotionally hard knowing she should be there."

Spierer, a fashion merchandising major who had just completed her sophomore year, was last seen early the morning of June 3, 2011, on the intersection of 11th Street and College Avenue in Bloomington, according to one of the woman's acquaintances and college classmates.

That acquaintance, identified as Jay Rosenbaum, claims he watched Spierer walk from his building toward her off-campus apartment complex some three blocks away around 4:30 a.m. the morning she disappeared. Rosenbaum’s last reported sighting of Spierer followed a night of partying among a group of college friends and acquaintances.

Nearly two years later, Bloomington police continue to actively investigate the case, but no arrests have been made to date -- and several leads have led nowhere.

On Monday, a coroner in neighboring Brown County told FoxNews.com that human remains found last week in a rugged area are being examined for identification.

Brown County chief deputy coroner Earl Piper said the partial remains were discovered on private property by two women looking for mushrooms and were there for "probably a couple of years." He could not confirm whether the remains were male or female. Piper said some clothing was found among the bones, but declined to describe it.

The remains were found on a ridge that is "quite a hike up" from a rural road, Piper said. The area is approximately 19 miles from the Indiana University campus in Bloomington.

Piper said an anthropology team examining the bones should have results by early next week.

"They’re looking for any traumatic injuries," he said. "They need to establish the cause of death first and then they will work to make an identification."

Robert Spierer has said that his daughter, who took medication for a heart condition, could have been drugged at Kilroy’s Sports Bar, a popular college hangout with an outdoor sandy area designed to look like a beach. Authorities reported that Spierer left her shoes and cellphone behind there.

“She could have been given something in her drink, unknowingly, that made her almost incapacitated,” Spierer said in an interview last year.

Spierer left her apartment complex around 12:30 a.m. June 3 with a friend, David Rohn, to walk to Rosenbaum’s apartment. Once at Rosenbaum’s residence, Spierer met a male acquaintance – Corey Rossman – who lived two doors down from Rosenbaum.

Rossman, who was reportedly on a "no trespass" list at Spierer’s building over a 2010 incident that had occurred there, left his building with Spierer and headed for Kilroy’s Sports Bar. Police said Spierer and Rossman entered the bar at 1:46 a.m. and left at 2:27 a.m.

Many questions surround what happened next.

Surveillance video captured Rossman and Spierer entering her apartment building – known as Smallwood – shortly after leaving the bar. Rossman reportedly claimed he was injured in a fight with other male students on the fifth floor of the building and remembers nothing of what happened during and after the incident. At 2:42 a.m., Spierer is seen leaving her building with Rossman and walking up an alley toward Rosenbaum and Rossman’s apartment complex.

Spierer, who police say dropped her keys and identification card on the way, spent some time at the men’s building before leaving at 4:30 a.m., according to Rosenbaum, who claims he watched from a balcony as she walked toward her apartment. Spierer was never seen or heard from again.

Do the young men who last saw Spierer alive know her fate? Or did she fall victim to a stranger abduction as she walked in the dark, alone and inebriated, a short distance toward her home?

Bloomington police say they have not ruled out any theories and continue to pursue leads received by the department.

"Since the time of Lauren's disappearance on June 3, 2011, the Bloomington Police Department has continued its ongoing effort to provide answers to Lauren's family and the Bloomington community," Capt. Joe Qualters said in a statement. "Despite being nearly two years into this investigation, information continues to come in regarding Lauren's case and investigators diligently pursue the information with the same level of commitment as in the beginning."

"No amount of time passing will deter us from our responsibility and we remain dedicated to Lauren's cause," he said.

Spierer’s disappearance touched off a massive search by air, land and water for any trace of the young woman. Bloomington firefighters this week rebuilt 20 weathered billboards featuring Spierer's image. They are also hanging new posters of the woman in the area in the hopes it will trigger more leads.

"If there is a silver lining to the nightmare we have been living since Lauren’s disappearance, it has been the opportunity to meet so many genuine, caring people from Bloomington who have been unwavering in their support, and committed to helping us in any way they can," Robert and his wife, Charlene, posted on their Facebook page Monday.

Spierer, who is 4-foot-11 and weighs 95 pounds, has blonde hair and blue eyes. She was last seen wearing black pants and a white top.

A $250,000 reward is being offered for any information leading to Spierer’s whereabouts. Anyone with tips in the case is urged to contact the Bloomington Police Department by phone at 812-339-4477 or by email at policetips@bloomington.in.gov.

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