The University of Wisconsin-Madison sophomore who was missing for more than four days last week faked her abduction, police said Friday.

“We do not believe there is a suspect at large, period,” said Assistant Madison Police Chief Noble Wray at a press conference.

Police found Audrey Seiler, of Rockford, Minn., Wednesday in a marsh less than two miles from her apartment where she was last seen at 2:30 a.m. on March 27.

Police said Seiler, 20, lied about her abduction and planted a knife, duct tape and rope in the marsh where she was found.

Wray said the initial finding of those items gave some credibility to Seiler’s abduction story until they later obtained a store surveillance tape that showed Seiler purchasing those items prior to her disappearance.

Other inconsistencies in Seiler’s story include: finding information on her computer related to Internet searches for Madison’s wooded areas and five-day weather forecasts, police said.

Wray said police do not know why Seiler staged the abduction.

“It is difficult for me to speculate about her mental state, why she would do this,” he said.

The “Dateline NBC” news program reported Friday that Seiler was in a psychiatric facility.

University of Wisconsin-Madison junior Dan Klepack said many of his fellow students have questions about the false abduction claims.

Klepack said many frustrated students are starting to joke about Seiler’s claims.

“People were running around (on campus Friday night), goofing around and yelling ‘Where’s Audrey?’ ” he said. “It’s like a huge joke now, but obviously you have to feel bad for her.”

Close friends of the Seiler family were supportive of Seiler.

“Our whole family is not doing well at this point,” said David Fisher, brother of Seiler’s boyfriend, Ryan. “But we love her. Whatever happens, we’ll love her through whatever.”

Other close friends of the Seiler family did not return phone calls.

Approximately 150 police officers combed the area for an alleged suspect after she was found.

Police estimated costs for the intensive manhunt will exceed $70,000, said Melanie Conklin, a spokeswoman for Mayor David Cieslewicz.

Wray said the department is still investigating the case for any remaining leads and declined to comment if Seiler will face charges for lying to the police.

Filing false claims to the police is a maximum of a misdemeanor crime, said Ron Reier, public information officer for the Minneapolis Police Department.

Reier estimated that the total cost of the investigation of Seiler’s disappearance might be as high as $1 million, and he said there is no way Madison police can get it back.

“Police departments are in the business of solving crimes, and there is no way we can go after people civilly, nor could the city of Madison,” he said.

Rick Martinson, a neighbor and close friend of the Seiler family, refused to comment to The Minnesota Daily at the request of the Seiler family but told the Star Tribune he did not care what it cost to find Seiler safely.

– The Associated Press contributed to this report.