Six people were killed Tuesday when a Greyhound bus and two semitrailer trucks were involved in an accident on I-80, 40 miles east of Park City, the Utah Highway patrol said.

"We've got six fatals, these are unconfirmed. I don't have a count on injuries. The injured are being transported to Evanston," said Gary Whitney, UHP public information officer.Blaine Whimpey, of Morgan, was driving to Evanston, Wyo., and arrived at the accident scene minutes after the crash. He said two semis, one filled with a cargo of hams, blocked the highway, while the bus was overturned on the shoulder of the eastbound lane. Traffic was backed up for several miles in each direction, and onlookers directed injured victims into the waiting cars for warmth.

"I could see the bus. There were people up on top of the bus pulling people out. Everybody that came out of the bus that I had seen was hurt, broken arms, legs, cuts.

"We were just grabbing people and walking down the road and throwing them in cars.

"They were just all moaning and groaning and freezing. They wanted a warm place to get into. Of course, everybody was in shock."

LDS Hospital dispatched two helicopters and an airplane to transport injured passengers. As many as 32 people have been transported to the emergency room at an Evanston hospital, said LDS Hospital spokesman Craig Rasmussen.

"We have a Greyhound bus on its side, and two semitankers involved," Whitney said. "I don't know what happened or how they got mixed up. We got our first call at 9:35. The accident happened sometime not long before that."

Greyhound dispatcher Bill Moore said Bus No. 1314 left Salt Lake City at 8 a.m. en route to Chicago with more than 40 passengers aboard. But Greyhound and UHP could not confirm that bus No. 1314 was the bus involved in the accident.

He had no word on injuries but said Greyhound had dispatched adjusters and inspectors to the scene about seven miles from the border.

A Utah Highway Patrol dispatcher in Coalville, Utah, confirmed the accident had occurred and that troopers were en route, but she had no further details.

The Wyoming Highway Patrol said it was notified of the accident at 9:41 a.m. and extrication vehicles from Evanston had been sent and that ambulances were on the scene.

Officials at Evanston Regional Hospital, about 10 miles from the accident site, said injured people from the accident were arriving, but there was no one immediately available to give details.

The Wyoming Army National Guard armory in Evanston has been opened for travelers who were on the bus, according to Sgt. Bob June, unit administrator for Battery C, 3rd Battalion, 49th Field Artillery.

"We're allowing people, I guess, to use the armory, to stay here until they can find transportation elsewhere or whatever," June said.

The sergeant was not told how many people to expect, and as of 10:45 a.m. none had arrived.

Meanwhile, blowing, drifting snow, blowing sand and black ice created hazardous driving conditions in Box Elder and Cache counties Tuesday.

And much of the rest of the state will be hit with a cold winter storm beginning Tuesday night and continuing through most of the rest of the week, according to the National Weather Service.

"It looks like the whole North Pole will be dumping cold and very wintry conditions on Utah," said William J. Alder, meteorologist in charge of the Salt Lake office of the National Weather Service.

A Utah Highway Patrol and Box Elder County sheriff's dispatcher said that by midmorning Tuesday I-84 was open northwest of Tremonton to the Idaho border but was closed north of the border.

Icy and extremely hazardous roads were reported in the area, where blowing sand was greatly restricting travel, the dispatcher said at 10:45 a.m.

The Idaho Department of Transportation reported drifting snow, pushed in some areas by high winds, was creating problems on major routes around that state.

Earlier Tuesday, a Utah Highway Patrol dispatcher said there was at least one rollover involving a semitrailer truck west of Tremonton. Apparently no one was injured in the accident, which occurred shortly after 3 a.m. west of Tremonton on I-84.

I-15 from Tremonton north through the Malad area also was reported slick and hazardous in some places.

Sardine Canyon, located between Brigham City and Logan, was snowpacked and slick, but open to traffic at 9:45 a.m.

A patrol dispatcher in Logan said travel in Cache County remained hazardous by midmorning Tuesday, particularly on the west side of the valley.

"We've had a lot of fender-benders but nothing major. A lot of cars are off the road. We haven't had a lot of new snow. It's mainly a problem of blowing snow already on the ground," the dispatcher said shortly before 10 a.m.

The National Weather Service said wind gusts of up to 61 mph were reported in Cache Valley. Gusts to 52 mph were reported on I-84 at the port of entry near the Idaho border, while a 41-mph gust was clocked at Kearns in southwest Salt Lake County.

Blowing dust reduced visibility to near zero on sections of I-84 between Burley, Idaho and the Utah border, weather service meteorologists said Tuesday morning.

The storm that hit the extreme northern section of Utah was expected to move south Tuesday, bringing snow and colder weather to much of the rest of the state.

As the storm continues to strengthen, snow is expected to develop in northern Utah late Tuesday and over most of the state except for the Dixie area Wednesday.

Two to 4 inches of snow are expected in some valleys and 12 to 18 inches of snow in the mountains by Wednesday.

Temperatures will begin plummeting late Wednesday and Thursday as cold Arctic air associated with the system moves to move into Utah, said Dean Jackman, deputy meteorologist in charge of the Salt Lake office of the National Weather Service.

Alder and Jackman said travelers should be aware of the potential for dangerous weather conditions and be alert for strong winds. Highways may become slick and snowpacked in local areas from drifting, and motorists are likely to come upon these areas without much warning, the meteorologists said.