Police in Kansas City, Missouri, confirmed this week that missing college student Toni Anderson — who vanished in January after sending a cryptic text to a friend — was found dead in a car that was pulled from the Missouri River last week.

Authorities say Anderson’s car had been submerged for weeks after she accidentally drove into the water soon after going missing early on Jan. 15.

Anderson, 20, left work at the Chrome club in Kansas City just after 4 a.m. that day and was on her way to meet up with a friend. But police say she never made it.

She was pulled over at 4:30 a.m. by a North Kansas City, Missouri, police officer — a separate jurisdiction from Kansas City — for a routine traffic stop for an illegal lane change, which resulted in a warning.

Police said she then stopped for gas, and her mother, Liz Anderson, previously told PEOPLE her daughter’s debit card was declined at 4:33 a.m.

At 4:42 a.m., Toni texted a friend, “OMG just got pulled over again.” It remains unclear if she was referring to the 4:30 traffic stop or a subsequent one. She wasn’t seen alive again.

A police spokeswoman tells PEOPLE detectives have found nothing to suggest foul play factored into Toni’s death. The spokeswoman declined to discuss the case in detail, citing the department’s ongoing investigation.

But mom Liz Anderson says authorities have assured her the college sophomore’s death was accidental — though it seems her daughter tried to escape the water.

“I am relieved that it was nothing more than a tragic accident,” Liz tells PEOPLE.

“There was no foul play; had no broken bones, and there was nothing on her body that would indicate any type of a struggle,” she says. “It is horrible. But they finally found her and now, we have a bit of closure.”

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Investigators are waiting on autopsy results, which may provide them with additional information about how Toni died, the police spokeswoman says.

Toni’s mother says she probably became confused while driving in the dark that morning — steering her car onto a boat launch and into the frigid water.

Toni’s 2014 Ford Focus had a tracking device that sent out pings every eight or 10 seconds. On the morning of her disappearance, the tracking device sent out its final ping from a gas station not far from where her body was recovered.

“ believe she was confused and was turning around in a park, and that her GPS may have directed her to go the wrong way,” Liz says.

“If you look at the boat ramp she drove off of, it looks like a regular road — especially at night, when it’s dark,” she continues. “The police believe the ramp was icy and that she may have tried to stop but the car went into the water.”

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There were signs that Toni tried to get out of her car once it began sinking.

“The police told me that her window was down and that her seat belt was off, so they figure she was trying to get out,” Liz says. “The current of the river was too strong and the cold water rushed in just too quick for her to escape. That’s what the police have determined.”

Toni, whose body has been cremated, will be laid to rest on Tuesday during a funeral scheduled for 11 a.m. inside the Risen Savior Lutheran Church in Wichita, Kansas.

Toni studied marketing at the University of Missouri-Kansas City and, in her spare time, reviewed music festivals, according to her family. Her mother has described her as “a beautiful, smart, intelligent, hard-working, kind and loving person.”

“We are all just a mess right now,” Liz tells PEOPLE after confirmation of Toni’s death, “but we are surviving and getting through. We miss her so much.”