In an especially dramatic example in Minnesota of a newer technology halting a serious crime, authorities say a 15-year-old girl ended years of sexual assault when she texted to 911 from a moving semitrailer truck in western Minnesota that she had just been raped again by the driver.

Law enforcement stopped the semi on an interstate, rescued the teen and jailed the driver, who was charged Wednesday with first-degree criminal sexual conduct.

The rolling crime scene stretched along Interstate 94 for 110 miles or more last Monday, from Stearns County in central Minnesota to within 15 miles of North Dakota, according to the Sheriff's Office in Clay County, where the trucker was apprehended.

Kenneth G. Zehnder, 34, of Lexington, Mich., was returned the next day to Stearns County, appeared in court and remains jailed in lieu of $40,000 bail ahead of a court hearing on Thursday.

The teen's texts not only freed her from Zehnder's latest attack, the charges said, but also ended what she later said were numerous sexual assaults in the past week while on the road, and at least three years of his assaults at her home in Michigan.

Text-to-911 debuted in Minnesota in December 2017.

"Our preference is to always get a voice call," said Stearns County Chief Sheriff's Deputy Jon Lentz. "But if you are unable or it's too dangerous to make a 911 voice call," texting can be crucial.

In this case, Lentz said, "it worked as it was designed to do and led to a very good outcome."

In its first year across Minnesota, dispatchers fielded 4,860 texts for help. Among the more harrowing, according to the state Department of Public Safety (DPS), was a woman who texted 911 and said she was forced at gunpoint to drive a stranger from Orono to St. Paul with her young daughter in the car. Her text-to-911 ended with her captor's arrest.

In another instance, a hunter got lost in the woods on a cold night in Beltrami County and didn't have enough signal strength to call 911, but there was enough to text 911.

The technology has also proved crucial in Minnesota for people who are deaf, said Dana Wahlberg, director of the DPS' division of Emergency Communications Networks.

A group of deaf boaters became stranded on a Mille Lacs County lake when their motor gave out and just as temperatures started to drop, Wahlberg said. The boaters texted 911 and were rescued by state conservation officers.

The first text-to-911 was sent in 2009 in Iowa. As of last fall, federal data showed more than 1,600 emergency call centers nationwide could receive text requests for 911 services, up from about 650 two years earlier. Still, that's barely a quarter of the 6,400 across the country.

According to the Clay County Sheriff's Office and the charges against Zehnder:

About 10:25 a.m. last Monday, emergency dispatch in Otter Tail County started receiving texts from someone who said she was in a semi and had been sexually assaulted by the driver. She relayed that the truck was heading west on I-94, and she gave authorities a vehicle description.

A state trooper saw the westbound semi near Downer in Clay County and forced the driver to the shoulder.

The teenager was taken from the truck to a nearby hospital for examination, and Zehnder was arrested.

The teen said Zehnder raped her last Monday after he parked at a rest stop between 7 and 7:30 a.m. Within a few hours, she started texting 911.

Paul Walsh • 612-673-4482