SALT LAKE CITY — Police are serving search warrants and hunting for any clues about the mysterious disappearance of a University of Utah student, including basic details about a person she met when she was last seen.

Salt Lake City assistant Police Chief Tim Doubt said Tuesday the person who met 23-year-old Mackenzie Lueck could have been a man or a woman based on the vague description investigators have.

Lueck was last seen June 17, when she took a Lyft car from the airport to a park located miles from her apartment. Police say she didn't seem distressed when she met with someone at about 3 a.m.

Missing Student-Utah poster
This undated missing persons poster provided by the Salt Lake City Police shows Mackenzie Lueck, 23, a senior at the University of Utah, who was last seen a week ago.

Police say they don't have evidence of foul play, but are worried because she's missed classes and a flight to California. The Lyft driver has been cleared.

Missing Student Utah posts
A jogger runs pass a poster of Mackenzie Lueck at Liberty Park Monday, June 24, 2019, in Salt Lake City.