Lauren Spierer Search: Indiana Body Not Missing College Student

VIDEO: Groups search for missing Indiana University student on "Find Lauren Day."
WATCH Volunteers Search for Lauren Spierer

The body found in an Indiana creek Sunday is not that of missing college student Lauren Spierer, the Marion County Coroner's Office in Indianapolis said today.

"It appears as though this is an African-American female and not that of Lauren Spierer," Chief Deputy Coroner Alfie Ballew said.

A forensic pathologist and forensic anthropologist have determined that the "physical structural characteristics" of the body, including bone structure of the face, dental structure of the mouth and hair on the head, indicate that the body does not belong to Spierer.

The autopsy is ongoing and the coroner's office will work with the Indianapolis Police Department to determine the victim's identity and cause of death. While the process, which will involve microscopic sampling, might take up to several weeks, the cause of death might never be determined.

"Sometimes, you are unable to determine cause of death on a severely decomposed body," Ballew said.

The body was discovered Sunday night at Fall Creek, located about 65 miles north of Bloomington, Ind., where missing Indiana University student Spierer was last seen June 3.

Witnesses reportedly spotted the body floating in the water at the creek's edge just before 7 p.m.

Initially, authorities in Indianapolis were unable to provide identity, age or race of the badly decomposed female body found in the creek.

The Indianapolis Metropolitan Police had also contacted authorities in Noblesville, Ind., who are investigating the June 13 disappearance of 74-year-old great-grandmother Dorothy Heard, the Associated Press reported.

"Once we find out who she is, then we can backtrack and try to determine the events that led to her demise," said Kendale Adams, Indianapolis police public information officer to ABC's local affiliate WRTV.

Spierer was last seen at 4:30 a.m. at the intersection of 11th street and College Avenue, walking home to her apartment after a night out at Kilroy's Sports Bar and, later, a friend's party. Surveillance footage from her apartment at Smallwood Plaza shows that she never returned home. The last trace of the missing student was her keys, found one block away from where she was last seen.

Police in Bloomington have named 10 persons of interest in their ongoing investigation, including Jesse Wolf, Spierer's boyfriend who first reported her disappearance, and Jason Rosenbaum, the last person to admit seeing Spierer.

Rosenbaum became the center of attention when reports surfaced that he had left his Bloomington condo in the middle of search efforts. Rosenbaum's attorney, James Voyles, said in a news statement that "Mr. Rosenbaum has fully cooperated with the investigation of the disappearance of Lauren Spierer and will continue to do so."

A social media effort was launched by supporters and friends to spread the word about Spierer's disappearance and aid in her recovery efforts. A Facebook page, Twitter feed, website and blog have provided updates about the ongoing investigation.

@NewsOnLaurenS tweeted this morning that: "Regardless of results, a family will need our thoughts and prayers today."

Sunday marked once month since the 4-foot-11, 95-pound fashion major disappeared.