Senior Hannah Wilson’s death has officially been ruled a homicide, Brown County Coroner Earl Piper said. Her cause of death was blunt force trauma to the head.

Wilson, 22, was found dead in Brown County on Friday after having gone missing Thursday, April 23. She was a senior psychology major and was in Gamma Phi Beta sorority. She was originally from Fishers, Ind.

The investigation is ongoing, and once all the facts are known by the Brown County Prosecutor, a probable cause affidavit will be submitted to the Brown County Prosecutor's Office, according to an April 25 ISP release.

No new information on the case will be released until the investigation is complete.

Piper said he estimates she had been dead for roughly 4 to 7 hours when she was found at 8:30 a.m. in the Needmore area of Brown County.

Toxicology reports are pending and will take 10 to 14 days to process, Piper said.

In joint cooperation with the Bloomington Police Department, ISP detectives arrested Daniel E. Messel, 49, of Bloomington.

He is being held on a preliminary charge of murder.

Messel has a criminal history. In 1995, he was charged with operating a vehicle while intoxicated and endangering persons, according to mycase.in.gov.

Messel has also been charged with multiple counts of battery. In 1996, Messel was sentenced to 8 years in prison for battery by means of a deadly weapon and battery resulting in serious bodily injury.

“The entire IU Bloomington community mourns the tragic death of Hannah Wilson," IU spokesperson Mark Land said in an email. "Our deepest sympathies go out to Hannah’s family and friends during this unspeakably sad time.”

Through social media, IU urged people to stay safe.

"Students, please watch out for each other, especially tonight," IU said in a tweet. "If you feel your safety is at risk or see someone who needs help, call 911."

ISP urges anyone who has information related to Wilson's activities before she was reported missing to call ISP Bloomington at 812-332-4411.

Check back on idsnews.com for more updates, and follow us on Twitter at @idsnews.

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