Salt Lake City police are searching for a University of Utah senior who has been missing for a week, though at this point, they do not suspect foul play.

Mackenzie Lueck, 23, landed at Salt Lake City International Airport early on June 17 after visiting family in California. She took a Lyft to Hatch Park in North Salt Lake and met up with another person in a car, police said. That, according to police, was the last time Lueck was seen.

Salt Lake City Police Department Detective Greg Wilking told USA TODAY that law enforcement believes that meeting was "cordial."

"It seemed like she was a willing a participant in meeting up with this person," Wilking said. "We don’t have any reason to believe there’s foul play."

Since Lueck has been missing, Wilking said she's missed a flight back to California for a wedding. He added that the department's level of concern rises with each day it doesn't hear from Lueck. Police have opened a tip line for the case.

"We are actively following up on any leads that come in and actively searching for her," Wilking said.

Lyft said the route that Lueck's driver took contained no irregularities and ended at the destination as originally entered by the rider. The driver continued providing rides immediately after Lueck's ride, Lyft said.

"We recognize how scary this must be for those who know and love Ms. Lueck," a Lyft spokesman said in an email to USA TODAY. "The safety of our community is fundamental to Lyft and we are actively assisting law enforcement with their investigation."

Wilking said that in the past, there have been cases where people have gone "off the grid" and don't want to be contacted by family. If that's the case, the police department asks Lueck to contact authorities.

Wilking said the SLCPD will respect Lueck's privacy if she doesn't want to be contacted by family.

"She is an adult," he said. "She has that right, as an adult, to basically check out, if she wants."

The University of Utah released a statement on Monday about Lueck's disappearance, saying she is enrolled part-time at the university and studying kinesiology and pre-nursing while minoring in health.

"The university’s dean of students has spoken with Mackenzie’s family to offer support and to express the campus community’s shared hope for her safe return," the university said. "The dean’s office is also talking with and providing support to Mackenzie’s classmates."