Power was restored to government buildings, schools and other facilities late Tuesday after a 'major cable failure' shut down Detroit's public lighting grid and caused parts of the city to go dark, officials said.

The city announced at 5:15 p.m. Tuesday that all customers affected by the outage had their power back.

The Detroit Free Press reported that all of the Detroit's Public Lighting Department's roughly 100 customers, that mainly include large municipal buildings, had been affected.

Mayor Mike Duggan said the power grid hadn't been modernized in decades in Detroit, which is emerging from the largest municipal bankruptcy in U.S. history.The power was out at several major city buildings, such as the Joe Louis Arena and the Detroit Institute of Arts. 

Detroit Fire Chief Jack Wiley told Fox 2 that all firehouses experienced power outages, but some had generators. He said many crews were responding to reports of people being stuck in elevators. The outage happened about 10:30 a.m. 

All Detroit public schools dismissed at their half-day dismissal times due to the outage.

Assistant Superintendent Steven Wasko said some schools did not lose power but to avoid any confusion, such as for families with siblings at multiple schools, all schools would dismiss early, MyFoxDetroit.com reported.

The Associated Press contributed to this report.