By Crimesider Staff CBS/AP August 22, 2018, 3:13 PM Mollie Tibbetts murder suspect Cristhian Rivera held on $5 million bond

MONTEZUMA, Iowa — The man accused of murdering a 20-year-old Iowa college student and leaving her body in a cornfield last month will be held on $5 million cash bond, a judge ruled Wednesday. Cristhian Bahena Rivera, 24, an undocumented immigrant who lives in Iowa, is charged with first-degree murder in the death of Mollie Tibbetts.

Tibbetts disappeared July 18 while out for a jog in her hometown of Brooklyn, Iowa. The search for Tibbetts ended Tuesday when investigators found a body believed to be Tibbetts about 12 miles from where she went missing.

Rivera had been held since Tuesday on a $1 million cash-only bond. At a hearing Wednesday, Magistrate Judge Diane Crookham-Johnson granted a state prosecutor's request to raise the bond amount to $5 million.

Assistant attorney general Scott Brown cited the "heinous" nature of the crime and Rivera's immigration status. Investigators said Tuesday that Rivera is a Mexican national who has been living illegally in the area for about four to seven years.

Rivera's lawyer, Allan Richards, said he plans to ask for a bond review hearing at a later date. He said his client is a young man who has no prior criminal history and has worked for a prominent local farmer for years.

During Tuesday's hearing, the judge denied a defense request to remove television cameras from the courtroom.

Cristhian Bahena Rivera, 24, is charged in the death of Mollie Tibbetts (R).

Iowa Department of Public Safety

Police sifted through more than 4,000 tips but say the big break came over a week ago when investigators obtained surveillance video of Tibbetts jogging and noticed a black Chevy Malibu following her. Police traced the car to Rivera and brought him in for questioning on Monday.

Investigators said he admitted to running behind and alongside Tibbetts.

Rivera says Tibbetts threatened to call police, and then blacked out. In an affidavit, police say Rivera told them when he "came to" he found Tibbetts' body in his trunk and "noticed blood on the side of her head." He "dragged Tibbetts on foot … to a secluded location in a cornfield." After the interview, police say, Rivera guided them to her location "from memory."

Rivera worked at a nearby dairy farm, owned by the family of local Republican leader Craig Lang. In a statement, the farm said Rivera passed a government screening that made him eligible to work. If convicted, Rivera faces life in prison without parole.

In a statement released Wednesday, Tibbetts' family said "Our hearts are broken."

"On behalf of Mollie's entire family, we thank all of those from around the world who have sent their thoughts and prayers for our girl," the statement said. "We know that many of you will join us as we continue to carry Mollie in our hearts forever."

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