KINDRED, N.D. -- A school bus driver was hospitalized Friday morning after a Kindred School District bus and a semi truck collided near here amidst heavy fog.

The crash happened about 9 a.m. Friday at the intersection of North Dakota Highway 46 and Richland County Highway 1, when a semi driver heading north on Highway 1 apparently didn't see the school bus traveling east on Highway 46 due to the foggy conditions, said Virgil Muscha, the Kindred fire chief.

Three other semi trucks then crashed after coming upon the site of the accident about 6 miles east of Kindred.

The school bus was one of two Kindred buses heading to a field trip, Muscha said. The other bus wasn't involved in the crash.

Three of the 32 students were taken to the hospital by parents after sustaining minor injuries, Capt. Bryan Niewind said. Three adults were also on the bus, he said.

The female bus driver sustained the most severe injuries, authorities said. Emergency crews worked for 40 minutes to pull her from the badly damaged front end of the bus, Muscha said. She was then taken to an area hospital by ambulance.

While the vehicle involved were heavily damaged, Niewind said the school bus driver's injuries aren't expected to be life-threatening.

"Any time you hear of school bus crash involving some semis, you think it's some kind of worst case scenario thing and you can see it's a pretty bad scene here but luckily, again, the bus driver was the most seriously injured person today, and it's non-threatening injuries at this point in time," Niewind said. "Luckily there was no fatalities that happened here today. That easily could have happened today with the conditions we had and the type of people we had involved in this crash."

The region was under a dense fog advisory Friday morning, as heavy fog was causing limited visibility. Niewind said visibility was reduced to about a quarter of a mile at the time of the crash.

None of the truck drivers' injuries were serious, Muscha said.

At 9:47 a.m., the North Dakota Department of Transportation and the Highway Patrol announced the temporary closure of Highway 46 between Interstate 29 and Kindred due to the accident. The road will be closed for a few hours, with hopes to re-open Friday afternoon, Niewind said.

Jerry Malett, of F&M Transport of West Fargo, was driving his semi west on Highway 46 when he saw a truck in the middle of the highway. Dense fog meant there wasn't enough time for him to stop."It had the highway blocked off, and I couldn't believe I saw it, it just looked unreal," Malett said. "Then I realized it was real, and I couldn't stop and I just blanked out."

Malett's truck was the first to collide after the initial crash between another semi and the school bus, he said. He didn't see the bus until after he exited his truck. Another truck involved in the accident struck Malett's truck in the rear moments after he collided with the other semi. He said he barely felt the impact of the truck striking him from behind.

Malett had visible scratches and some blood on him after the accident. He said he crawled out of his truck and sat in a ditch, still in shock at what had happened. He said he thinks he would have had time to stop if not for the fog.