BROOKLYN, Iowa (CBSNEWS/AP) — The reward for the safe return of Mollie Tibbetts, a missing University of Iowa student, has increased to $260,000. Crime Stoppers of Central Iowa said Sunday that the 20-year-old’s relatives believe she is alive but has potentially been kidnapped. They hope the money will help lead to her return, Crime Stoppers spokesperson Greg Willey said Sunday.

Tibbetts, 20, went missing on July 18 from her small hometown of Brooklyn, Iowa.

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Mollie Tibbetts (KCCI via CBS Newspath)

Investigators are being tight-lipped about the case, saying holding back basic details may help solve it. That includes saying whether they believe Tibbetts returned home from a jog the evening she went missing.

Willey said Crime Stoppers will protect the anonymity of tipsters who call in or submit tips online. He said the organization has shared more than 200 anonymous tips with law enforcement since Monday.

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Investigators have searched through nearby cornfields and a pig farm to no avail. They’ve also been using digital forensic searches of her social media accounts, cellphone and fitness tracker in an effort to find her.

Fox News reports that FBI investigators spoke with the owner of the pig farm on two occasions. Wayne Cheney, who lives several miles away from Tibbetts’ home, told Fox News that agents have searched parts of his property, his home and cellphone. He has not been charged with a crime and said he doesn’t know Tibbetts.

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