MADISON, Wis. -

Two people were killed and more than 50 others were hurt on Sunday afternoon after dozens of cars were involved in two separate pileups on a foggy stretch of Interstate 90 just east of Madison.

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The Wisconsin State Patrol shut down Interstate 90 in both directions for hours, causing a traffic backup for miles. The highway reopened early Monday morning.

Flares were lining the interstate's lanes cut through the fog as traffic crawled north of the crash sites. Visibility was about 100 yards. Squad cars and tow trucks streamed toward the crashes as law enforcement agents directed drivers off the interstate.

About 10 agencies from around the region responded to the crash with nearly 75 to 100 emergency workers, not including police officers. Some emergency workers said that the pileup looked like a war zone, WISC-TV reported.

Madison Fire Department spokesman Eric Dahl said on Sunday that crashes continue to happen on the foggy highway even as emergency workers work to clear the road and move the injured to hospitals.

The incidents happened on a stretch of eastbound I-90 running south, near Sigglekow Road, from the Badger Interchange with Interstate 94. Authorities said that the pileup was concentrated near the 143 and 146 mile markers on I-90, affecting a roughly five-mile span. The Wisconsin State Patrol said that the pileup began at about 2:23 p.m.

Authorities said that the crash apparently began as some drivers began to slow down as fog rolled in. Then, other drivers didn't see traffic slowing and vehicles began to ram into each other in a domino effect, WISC-TV reported.

Lt. Laurie Steeber, of the Wisconsin State Patrol, said that there were two major crashes involving 25 and 26 vehicles, and a series of other ones. She said that some 50 people were taken to area hospitals, including three with life-threatening injuries.

Authorities said that the preliminary investigation shows that some motorists were traveling at least 70 mph -- above the 65 mph speed limit.

Steeber said that with the foggy conditions, people should have slowed down.

She said that it's too early to say whether any charges or citations would be filed.

Authorities released the identities of the two people killed on Monday morning. Delbert Smet, 79, of Fond Du Lac, was killed in a five-car crash near Highway N southeast of Madison. The State Patrol said that crash involved three cars and two tractor-trailers. Four other people were hurt in that collision.

Beatrice Winrich, 54, of Stoughton, was killed in another crash near the DeJope casino. The State Patrol offered no details on the circumstances of that crash.

The Red Cross has set up a hot line so people can call in to check on their family members. The phone number is 608-233-9300.

Authorities said that accident reconstruction people were at the scene on Sunday to piece together how the pileup occurred.

The fog continues to linger over parts of Wisconsin on Monday

Victims Taken To Area Hotels

Many of the people involved in the crashes were taken to area hotels so authorities can assess them.

More than 150 people were taken by Madison Metro bus to the Wingate Inn near Madison. The hotel, which is located near the scene of the massive pileup, became a shelter for those involved in the series of crashes.

Even hours after the afternoon pileup in thick fog, dozens of people filed into the hotel, clutching their children and belongings as State Patrol investigators interviewed them.

The Red Cross provided snacks and counseling. Officials also set up an aid station in the hotel lobby for people who were injured.

Sharon Hatch and her two children got out of their car when the vehicles started to pileup. Hatch said that she planned to stay overnight at the Wingate.

Many Victims Taken To Area Hospitals

Officials said on Monday morning that two people critically injured in the massive interstate pileup near Madison were improving.