Beloit Memorial Hospital said at least 27 people were treated for injuries sustained in the crash, WIFR-TV reported.

The extent of their injuries was not immediately clear, the station said.

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State Patrol officials said snow, ice and whiteout conditions were factors in the crash.

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Most of southern Wisconsin remained under a winter weather advisory Friday afternoon with more snow expected Saturday.

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The crash occurred at around 12:30 p.m. in Rock County between Janesville and Beloit, the State Patrol said in a statement posted on its Facebook page.

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Troopers arrived to find the interstate blocked in both directions.

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Troopers diverted traffic onto side roads. The southbound lanes reopened just after 8 p.m., the State Patrol said on Twitter late Friday.

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WIFR-TV posted live video of the scene just before 4 p.m. showing semitrailers backed up as emergency workers assisted motorists.

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