SIOUX FALLS - A strong spring storm has made travel hazardous in much of South Dakota, shutting down schools, delaying some local elections and hampering construction projects.

Over 10,000 residents are without power due to a combination of wind and ice on power lines.

According to Jim Clarke of Excel Energy 30 crews, some from as far away as Minneapolis, are working to restore power. However, Clarke says it could take a couple days to restore power to all residents.

The National Weather Service has issued various storm advisories, watches and warnings for the state. Forecasters say the storm moving across the Rocky Mountains and Greats Plains packs up to 20 inches of snow, sleet, freezing rain and strong winds.

The Federal Emergency Management Agency issued a statement urging travelers to be cautious. South Dakota Transportation official Greg Fuller says spring storms aren't unusual, but they can be dangerous.

The storm comes a day after heavy snow created bad travel conditions in southwest North Dakota, leading to numerous accidents. An oil tanker crashed near South Heart and spilled what authorities called a minimal amount of oil.

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