Why the FBI thinks Mollie Tibbetts' Fitbit could help find her

Mike Kilen | The Des Moines Register

Show Caption Hide Caption Brother of missing Mollie Tibbetts: 'Our hope is she comes home safe' Jake Tibbetts, brother of missing University of Iowa student Mollie Tibbetts, is hopeful for her safe return.

Investigators are sifting through electronic data from social media accounts and a physical activity tracker to help them in the search for Mollie Tibbetts, the 20-year-old from Brooklyn, Iowa, who has been missing for one week.

More: For the latest on the Mollie Tibbetts search, download the Des Moines Register app for your smartphone and tablet. iPhone | Android

The avid runner always wore a Fitbit, which tracks the distance traveled and other information. She was seen running the night she disappeared, while dog-sitting at the home of her boyfriend and her boyfriend’s brother in Brooklyn.

The Federal Bureau of Investigation has several agents dedicated to the case because additional expertise is needed in forensics to explore the areas around Brooklyn and in high technology to gather information on cell phones, social media and Fitbit, said Mitch Mortvedt, assistant director of the Iowa Division of Criminal Investigation, a state agency investigating the case.

“We are getting a lot of information back from that process. We are very hopeful with the electronic data we are getting back,” he said. “We are relying on the FBI heavily because it’s an ever-changing world in technology."

More: 'She hated to be sad and hated others to be sad': Brotherly love for missing sister

With each passing day, Mortvedt said the possibility of it being an abduction looms larger.

“We haven’t ruled anything out," he said, "but it’s been a week so it’s more and more suspicious to us.”

Tibbetts' boyfriend Dalton Jack told the Register Tuesday that she sent a Snapchat message to him that night which he opened about 10 p.m., and the photo sent looked like she was indoors.

More: Mollie Tibbetts' boyfriend talks about the last message he received from the now-missing 20-year-old

Poweshiek County Sheriff Tom Kriegel said Wednesday that Tibbetts' boyfriend and brothers are not suspects, ABC News reported.

Volunteer search efforts that served to quickly comb the area were abandoned earlier this week in favor of FBI and DCI experts who are retracing areas she frequently ran with a more expert eye to possible evidence.

“She is a creature of habit and went the same routes, so we’re going back and covering those areas and interviewing people again,” Mortvedt said.

The Poweshiek County Sheriff’s Department has received numerous messages and tips from the public that agents are following up on.

Anyone with any information related to this investigation is encouraged to contact the Poweshiek County Sheriff’s Office at 641-623-5679 or tips@poweshiekcosheriff.com