BISMARCK, N.D. (AP) — Officials have reopened part of Interstate 90 in southern South Dakota, but travel remains difficult in much of the Dakotas due to a snow storm that also has caused power outages and school closures.

The eastbound lanes of I-90 remain closed from Rapid City to Chamberlain, but the westbound lanes have been reopened from Wall to Rapid City.

No travel is advised in most of western South Dakota. Travel alerts are in place in northeast and central North Dakota.

Many schools in the two states are closed or starting late.

In North Dakota, the Mor-Gran-Sou and Verendreye Electric cooperatives are working to restore electricity. At least 3,500 customers were affected Tuesday. The co-ops pulled restoration crews for safety when it got dark, with plans to continue work after dawn.

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