(CNN) — A University of Utah student who took a late-night Lyft ride from the airport last week has not been seen since, Salt Lake City police said.

After visiting family, Mackenzie Lueck, 23, arrived at Salt Lake City International Airport on June 17 and then took a Lyft to an address in North Salt Lake, Utah, where she was last seen in the early-morning hours.

READ MORE: Dixon Man Identified As Suspect Who Led Chase Through 4 Counties

Police said they have spoken with Lyft and the Lyft driver, and both have cooperated with the investigation. The Lyft driver confirmed the route Lueck took and said she was dropped off in North Salt Lake, police Sgt. Brandon Shearer said. Shearer said the location is not a residence.

Lyft said that the route had no irregularities and ended at the destination Lueck entered. The driver continued providing rides immediately after the ride ended, the company said.

“We recognize how scary this must be for those who know and love Ms. Lueck,” Lyft said. “The safety of our community is fundamental to Lyft and we are actively assisting law enforcement with their investigation.”

Authorities believe her phone has not been on since June 17 and haven’t been able to find its location, Shearer said. Police have not discovered any information that leads them to believe she has been harmed or is in danger. Still, they said they’re concerned for her welfare.

READ MORE: Modesto's Vintage Faire Mall Seeks Help Gathering Gifts For Kids

Lueck is a senior at the University of Utah and has missed exams since she’s been missing, her friend and sorority sister Ashley Fine told CNN affiliate KSL.

“She’s extremely dedicated. She would never miss her midterms or anything like that,” Fine told the Salt Lake City TV station. “She hasn’t been home. She didn’t show up to work, or anything.”

Lueck had been at a family funeral in California, and last texted her parents at 1 a.m. June 17 when she landed back in Salt Lake City, CNN affiliate KSTU said.

“Detectives have been working throughout the weekend & will continue to follow any/all leads,” police said Sunday night. “We are aware of info being shared by her friends & others about this case.”

Police asked that anyone with information on the case contact them at 801-799-3000.

MORE NEWS: CHP: Man Shot On I-5 After Reports Of Road Rage Incident In Sacramento

™ & © 2019 Cable News Network, Inc., a Time Warner Company. All rights reserved.