BLOOMINGTON, Ind. – A coroner said Saturday that an Indiana University student found dead in a rural area hours before she was reported missing had been fatally beaten in the head with an unknown weapon.

Authorities, meanwhile, were holding a southern Indiana man on a preliminary murder charge in the death of Hannah N. Wilson, 22, of Fishers, an Indianapolis suburb.

Daniel E. Messel, 49, of Bloomington was arrested Friday in the death of the IU senior, said State Police Sgt. Curt Durnil. Messel was being held at the Brown County Jail.

Police have not disclosed a possible motive or said whether Messel and Wilson knew one another. No additional details on the killing had been released by Saturday evening.

Brown County Coroner Earl Piper told The Herald-Times that Wilson died from blunt force trauma to the head. He said preliminary results of an autopsy performed Saturday show she was struck three or four times in the back of the head with an unknown object.

No weapon was found in the rural area where her body was found near Lake Lemon, he said. The coroner said Wilson’s only other injuries were superficial abrasions and bruises that he described as protective, rather than defensive, wounds.

“Like trying to prevent her head from being hit,” he told The Herald-Times.

Piper said Wilson had been dead several hours by the time her body was found Friday morning in Brown County. That county is just east of Monroe County, where IU’s campus is located in the city of Bloomington about 50 miles south of Indianapolis.

Bloomington police received a missing persons report on Wilson’s disappearance Friday afternoon, several hours before authorities identified the body.

Wilson’s death cast a pall over the Bloomington campus’ Little 500 weekend, when an annual men’s bicycle race is held and local bars fill up with revelers.

Friday night’s Little 500 festivities were canceled following the news of Wilson’s death. And on Saturday, officials postponed the day’s race, touted as the largest men’s collegiate bike race, until Sunday, because of thunderstorms and showers.

IU basketball player Yogi Ferrell also postponed his planned Saturday night announcement of whether he’ll enter the NBA draft, citing Wilson’s killing.

While bars were still packed in Bloomington on Friday night, outside Wilson’s Bloomington home friends were in tears and silently entered and exited the area, The Indianapolis Star reported.

IU spokesman Mark Land said “the entire IU Bloomington community mourns the tragic death of Hannah Wilson.”

“Our deepest sympathies go out to Hannah’s family and friends during this unspeakably sad time,” he said in a statement.

Hannah was a graduate of Hamilton Southeastern High School in Fishers, just north of Indianapolis, and was a member of the Gamma Phi Beta sorority.

Her death comes nearly four years after another IU student, Lauren Spierer, vanished after a night out with friends in the college town.

The 20-year-old Greenburgh, New York, woman was last seen on June 3, 2011. She has not been found and no criminal charges have been filed in her disappearance.

In May 2000, another IU student, 19-year-old Jill Behrman, vanished during a bike ride near Bloomington. Her skeletal remains were found nearly three years later in a remote field about 15 miles from the city.

In 2006, a jury convicted a local handyman, John R. Myers II, of Ellettsville, in Behrman’s murder. Myers is serving a 65-year prison sentence.