Detroit power outage December 2014 update: Shuts down 100 buildings in downtown area

"The city's public lighting grid suffered a major cable failure that caused the entire grid to lose power at approximately 10:30 this morning," the Detroit Public Lighting Department said in a statement.

Street lights were out for several blocks and buildings affected included the Joe Louis Arena, a courthouse and the Coleman A. Young Municipal Center, which includes city hall. Firehouses were running on backup generators.

Detroit Institute of Arts was hit by the outage and employees were escorting visitors out of the building, an official said. The websites for the Detroit Public Schools and Wayne State University said students were dismissed and classes were canceled for the day.

"We're not sure exactly where the outage is," DTE Energy spokeswoman Randi Berris said. "We do not know the cause."

DTE sells power to Detroit Public Lighting, which distributes it to public building customers. Berris said DTE advisors are working with the city to provide support.