The FBI joins the search for a student from the University of Iowa amid new fears that something has happened "against his will"

Mollie Tibbetts, a student at the University of University of Iowa, was reported missing in Brooklyn, Iowa on Thursday, July 19, 2018.

(Criminal Investigations Department of Iowa via AP)

The FBI and state investigators resumed Tuesday the search for a student from the University of Iowa gone missing for nearly a week and the authorities have stated that he "was leaning more and more on something against her." [19659004LesvolontairesàlarecherchedeMollieTibbetts20ansdeBrooklynIowaontétéretiréscettesemaineduFBIetdesenquêteursdel'EtatadéclaréMitchMortvedtunporte-paroledelaDivisiondesenquêtescriminellesdel'Iowapourl'aidedupublicNousaimerionsobtenirtouteslesinformationsquenouspouvonsPluslesyeuxetlesoreillessontnombreuxmieuxc'[19659004] – Mitch Mortvedt

Mortvedt said that officials "are looking more and more towards something happens to him against his will "

house last Wednesday, reported KCRG-TV. Her boyfriend, Dalton Jack, was 100 miles away on a construction site.

A neighbor said he saw jogging that night. Jack told the station that he had handed her a photo of Snapchat late Wednesday night, after she had returned home after her jog.

When he texted her Thursday morning, he replied that she was not answering. friends and family.

Investigators from the FBI and Iowa are now focusing on the areas around Brooklyn that Tibbetts frequented. The FBI is also studying Tibbett's online story and its use of a cell phone to determine where it could be, Mortvedt said.

Tibbetts was born in San Francisco and lived in Oakland until he arrived in Iowa with his mother. second year, the Des Moines register reported. His father, who lives in Fresno, allegedly flown to Iowa to help with research.

Dozens of volunteers in Brooklyn searched fields around Tibbetts and Jack's house. They also covered the area with missing posters, T-shirts and signs to try to find her.

Tibbetts 'aunt, Kim Calderwood of Brooklyn, told the Des Moines Register that Tibbetts' family was frustrated by the lack of progress. in research.

"We rack our brains, thinking of what we can think of telling investigators," she said. "It's the worst thing to want to fix something that you can not fix."

Associated Press contributed to this report.