Two explosions at Wisconsin’s only oil refinery have wracked the city of Superior, on the edge of Lake Superior. So far, there are at least 20 injuries reported.

ImagThe cause of the blasts are not yet known. Douglas County has declared a state of emergency. Thick black smoke is rising into the air for miles.

The city of Superior is being evacuated, with many residents heading toward Duluth, Minnesota. The refinery is still on fire.

Superior Fire Battalion Chief Scott Gordon says the department is waiting for reinforcements.