Fire at Black Dog power plant in Burnsville, Minn.

Xcel Energy confirmed one worker was injured in a morning fire at the Black Dog power plant in Burnsville, Minn. The fire started at about 7:30 a.m. in one of the power plant's coal bunkers.

About 50 people were evacuated, but later returned to work at the plant, which continued to operate during the fire.

The Black Dog plant was built in the 1950s as a coal-fired plant. The plant has since transitioned to a combination of coal and natural gas boilers. Two dual-fuel coal and natural gas boilers that use coal as the primary fuel source as set to be retired in April.