Robert Spierer was stoic as he thanked community members and police for an onslaught of support in the days since the disappearance of Lauren, 20.

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"She's full of life, always on the go, fun to be with, had a very large circle of friends, both boys and girls. She's the kind of person that would spend time volunteering," Spierer said.

Bloomington police Lt. Bill Parker said the search for Spierer began Friday afternoon, less than 12 hours after she was last seen, and that either foul play or a medical condition could be involved. She is 4 feet 11 inches tall and weighs 90-95 pounds.

Parker said searchers should not focus on Spierer's appearance in the most commonly spread picture of her with short hair. Authorities said her hair could be longer or it could have been cut or dyed.

Investigators reconstructed the hours before Spierer's disappearance. She had been at Kilroy's, a sports bar and had been at a friend's apartment before deciding to walk to her home at Smallwood Plaza at about 4:30 a.m.

Police determined that one of the woman's male friends was the last to see her as she walked barefoot at the corner of 11th Street and College Avenue, on her way toward her apartment.

"We've been interviewing everybody that was with her," Parker said. "They've cooperated fully with letting us search their places, their cars."

Spierer has a heart condition and needs medication. She had also been drinking in the hours before her disappearance, officials said.

Two separate searches have been ongoing in recent days, one conducted by police and another comprised of family members, friends and hundreds of volunteers. At least one police officer is involved in each of the volunteer searches.

"We very much appreciate the help that all the volunteers have provided," Parker said. "They would be very hard to cover with a small group of officers."

Lauren Spierer

The search for Spierer is further complicated because she did not have her cellphone with her, having left it at the bar earlier in the morning. Authorities have no way to track her.

Aside from Bloomington police, Indiana University police, the Monroe County Sheriff's Department, Indiana State Police and the FBI have provided assistance in the search, Parker said.

"We will continue these same procedures, but at this point, we don't have a revelation," Parker said. "We're inviting tips. We're inviting information."

Parker said there are no suspects in Spierer's disappearance.

"We don't have anybody that we characterize as a suspect," Parker said. "People that were with her are, of course, persons of interest."

Spierer hopes community members will keep up the search.

"There's a lot more we have to do to find Lauren," he said. "Continue to join us every day in front of Smallwood. There will be searches three times a day."

Those searches are starting at 10 a.m., 2 p.m. and 5:30 p.m. at Smallwood.

"If anybody saw Lauren on Thursday night with anyone, please share that with Bloomington police. It doesn't matter how casual it was," Spierer said.

The woman's disappearance has taken an emotional toll on her family.

"She's a loving girl, very close with her mother, spoke to her mother every day," Spierer said.

About 15 Indiana University ROTC members and their instructor were part of a volunteer search Tuesday morning. They were going through wooded areas that are more difficult for other people to comb.

Many of the people looking for Spierer don't know her, but they were moved by stories about her disappearance in recent days.

News of the search for Spierer spread globally, thanks to the Internet and coverage from outlets such as CNN and network news programs.

Spierer's family and friends have set up a website to assist with search efforts. There is also an active group on Facebook involved in the search for Spierer.

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