Mollie Tibbetts, a University of Iowa student who was last seen during an evening jog a month ago, was believed to have been found dead and an undocumented immigrant has been charged with her murder, authorities said on Tuesday.
Cristhian Bahena Rivera, 24, was charged with first-degree murder, the Poweshiek County Sheriff's Office said. Officials said a body had been found early Tuesday in a farm field southeast of Brooklyn, Iowa.
The identity of the body has not been confirmed, but it was believed to be Tibbetts.
“Our hearts go out to the Tibbetts family and to the Brooklyn community. It is a loss for all of us,” Poweshiek County Sheriff Tom Kriegel said in a news release.
Investigators said they used surveillance video to track down Rivera. The video showed Tibbetts, 20, jogging in a rural area near her hometown of Brooklyn, as well as Rivera's car.
Officials believe Rivera is from Mexico and had seen Tibbetts jogging in the past, according to NBC affiliate KWWL.
A massive search had been underway for Tibbetts, who vanished on July 18 and whose disappearance sparked national attention.
Dozens of volunteers in the town of Brooklyn, Iowa, which has a population of about 1,500, had been searching fields around her house and the house where she was staying. Searches were also conducted by ground and air, and the use of K-9s.
Crime Stoppers of Central Iowa offered a reward of nearly $400,000 for any tip that led to her safe return.
The surrounding area had been covered with missing person posters, T-shirts and billboards pleading for help in finding the missing woman.
Police were also scanning Tibbetts' digital footprint in an attempt to find her, Iowa Division of Criminal Investigation spokesman Mitch Mortvedt said last month. Tibbetts, an avid runner, often wore a Fitbit, according to her family.
Tibbetts' boyfriend, Dalton Jack, said he received a Snapchat message from her the night she disappeared after she would have returned from her run. She was reported missing the following day after she failed to show up for work.
Jack is not a suspect in the investigation. He was working a construction job about 100 miles northeast in Dubuque when Tibbetts went missing.
"She's not going to run off," Jack said in an interview earlier this month. "I try not to speculate on it too much because the only thing that comes into your head whenever you're not investigating all the facts is that something bad happened and you don't, I personally don't want to believe that."
Tibbetts was staying at Jack's home, where she was watching his dogs, at the time she went missing.