Xcel spokeswoman Mary Sandok it had not been determined what caused the 5 a.m. blast at the Allen S. King power plant facility in Oak Park Heights, the Star Tribune reported. Sandok said the company would likely keep the plant shut down for a couple of days to assess the damage and determine what happened.

No one was injured in the incident and no customers lost power, she told the Minneapolis newspaper.

The Oak Park Heights plant, located several miles east of the Twin Cities, generates 600 megawatts of electricity.