A college student was killed at a Mississippi rest stop on Tuesday when two tires came loose from a passing tractor trailer and struck the 21-year-old woman.

The Biloxi Sun Herald and other news outlets identified the victim as Margaret Maurer, of Minnesota. Maurer and two friends were about to get back into their vehicle at an Interstate 10 rest stop at the time of the accident, authorities say.

Police say the tires came from a tractor-trailer traveling westbound; the wheels crossed eastbound lanes and entered the rest stop, striking Maurer and two vehicles.

The tires — the rear dual tires of an 18-wheeler — were bolted together and weighed roughly 500 pounds, ABC News reports. The tires traveled more than 800 feet before striking Maurer, the network reports, citing police.

Maurer was a senior at Tulane University in New Orleans, where she studied ecology and evolutionary biology.

University president Mike Fitts described Maurer as an "extraordinarily gifted student and a leader among her peers" in a written statement.

"She was planning to graduate in May to pursue a career in scientific illustration – a field that combined her skill as a scientist, her incredible artistic talent and her love of nature," he said.

Speaking with Minnesota's KSTP-TV, Maurer's mother said the "freak accident" happened as her daughter and her friends took a restroom break during a spring-break road trip.

"It's absolutely a random freaky thing," Tracy Maurer told the station. "It's not right. There's so much that's wrong about this. It's just random. I really want to be angry at somebody, but I can't be."

The truck driver realized that something had detached from the vehicle and turned around to investigate, the Sun Herald reports. Police suspect no wrongdoing on the driver's part, the paper says.

Contributing: The Associated Press