Standard and Poor's Corp said it raisedto A from BBB-plus the preferred stock of MDU Resources Group
Inc.
    S and P affirmed the company's A-rated first mortgage bonds
and A-minus unsecured industrial revenue bonds. About 300 mln
dlrs of debt and preferred were outstanding at December 31,
1986.
    The rating agency cited recent redemptions that reduced the
layer of preferred in the company's capital structure. S and P
expects fundamentals to remain strong for electric utility and
natural gas pipeline and distribution units.
 Reuter
