(CNN) -- Three people were killed and a state trooper was seriously injured in a series of crashes -- involving up to 50 vehicles -- that shut down the Ohio Turnpike on Wednesday, according to the Ohio State Highway Patrol.
Trooper Andrew Clouser, 29, responded to a multiple-vehicle crash in Sandusky County around 1:25 p.m.
"While he [Trooper Clouser] was on scene he became struck and pinned between two cars, and after that other cars became involved. The exact sequence of how it all happened we won't know until at least tomorrow," said patrol spokeswoman Lt. Anne Ralston.
Clouser was in serious condition at Mercy St. Vincent Medical Center in Toledo, said Ralston. The number of other injuries was not clear.
Those stuck in the eight-mile-backup were being rerouted. Traffic in both directions was shut off late Wednesday.
Officials reported heavy snow and whiteout conditions.
Ralston said authorities were trying to clear one lane.
"A section of the crash involving three semis is the big problem because they have to get those out of the way to get that one way open heading eastbound," Ralston said.
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