The driver of an SUV that rolled into a ditch near Mankato, pitching his girlfriend to her death, said Tuesday that he was cut off by another vehicle and that the other motorist was angry and at one point flashed a profane gesture during a miles-long encounter.

The rollover occurred about 4:40 p.m. Monday on Hwy. 60 west of Lake Crystal, Minn., and roughly 15 miles southwest of Mankato, the State Patrol said.

Jalynn R. Williams, 20, of Mankato, was not wearing a seat belt and was thrown from the vehicle, the patrol said. She was hospitalized in Rochester and later died. Her boyfriend, Dennis R. Egge, 26, of Mankato, was hospitalized with noncritical injuries and later released.

“Jalynn waved at [the other driver] just to be nice, and he flipped us off and [messed] with us for a few miles,” Egge said. He said the two vehicles may have slightly touched at one point on the highway, which has two lanes in each direction.

“The last I saw … he was beside me,” Egge said. “A few minutes later … I hear Jalynn say ‘What the …?’ and then we were rolling.”

Said Egge, “She was my world.”

The couple had left her hometown in central Nebraska that morning and were minutes away from finishing the 450-mile return trip to Minnesota.

“The quicker we have answers, the better,” said Williams’ stepfather, Mason Schau, who lives in Mankato. “She turned 20 a couple of weeks ago. ... We’re all devastated.”

Williams moved from Cozad, Neb., and followed a brother to Mankato after graduating from high school in May 2018.

The State Patrol said the other vehicle was a Ford SUV but has not released specifics.

The patrol asks anyone who may have information about the crash to call its Mankato district office at 1-507-344-2750.