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Law enforcement search for armed suspect, Vance Boelter, in fatal shooting of Minnesota lawmaker.
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Minnesota River Valley's 3.6-billion-year-old rocks

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In The Daily Circuit's letters segment this week, a professor mentioned that the Minnesota River Valley is home to 3.6-billion-year-old rocks, some of the oldest rocks on earth. We follow up on why that would be and what they signify about Minnesota's past and future.

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