BROOKLYN, Iowa -- Investigators say they have searched a pig farm and other places in east-central Iowa near where a University of Iowa student went missing but have turned up no sign of her.
KCCI-TV reports the pig farm is near Guernsey, about 15 minutes from 20-year-old Mollie Tibbetts' hometown of Brooklyn, Iowa. Tibbetts was last seen the evening of July 18 jogging near her boyfriend's Brooklyn home, where she was staying to watch his dogs while he was out of town.
Tibbetts' boyfriend Dalton Jack has been ruled out as a suspect.
SEE ALSO: Missing college student Mollie Tibbetts: A timeline
"This is not like her," Jack told WOI-TV last week. "If this is her running off, nobody would've seen it coming. Nobody in the world. Not her family, not me -- nobody would've ever guessed that she just take off and not tell anybody."
Investigators are using forensic technology to scour Tibbetts' social media accounts, fitness tracker and phone for clues. As more time passes since Tibbetts' disappearance, authorities are increasingly suspecting that she was abducted.
"There's really no clues," Laura Calderwood, Tibbetts' mother, told "Good Morning America" in an exclusive interview on Friday. "There's a DCI agent who said she's been in the business for 23 years and only one other case where she had so few leads. So I really can't speculate. I'm just hoping for the best."
The Associated Press contributed to this report.