UPDATED 9:00 p.m.: For about four hours, an equipment failure in Charles County left the campus without power, while Facilities Management and Pepco officials worked to bring back electricity.

The campuswide blackout began at about 12:45 p.m., said Bill Olen, planning and construction interim executive director. Pepco, a major electricity provider for the Washington Metropolitan area, experienced an equipment failure in a substation in Charles County, which caused the incident.

University President Wallace Loh closed the school at 2 p.m. as Pepco and campus facility crews continued to work on the issue. Firefighters went from building to building to help those stuck in elevators.

Crews restored power to most of North Campus by 3:41 p.m. before reaching the whole campus by 4:50 p.m. It will take awhile for water heaters and generators to heat back up in dorms, University Communications Director Katie Lawson said.

Stamp Student Union closed at 4 p.m. and canceled all events, but a few of the restaurants in the food court continued to serve food until then, Stamp Director Marsha Guenzler-Stevens said. The Eppley Recreation Center also closed early and canceled its evening classes and programs, while the University Health Center closed shortly after power went out.

“After PEPCO was able to restore power to their substation we were able to restore power to the campus,” Jack Baker, executive director of operations and maintenance, wrote in an email. “We are checking all the campus system to insure [sic] everything came back on line.”

The busted transmission line on Ryceville Road in Charles County sent power outages rippling through nearby areas, Pepco spokesman Sean Kelly said. A broken insulator caused the transmission line to fall and break, and when it fell, there was a flash of light, a small fire and a loud sound that might have been mistaken for an explosion, he said.

This incident caused a “dip in voltage” to move through electrical systems in southern parts of this state and in Washington, including the White House, he said.

The fire was “nothing catastrophic,” said Bill Smith, Charles County volunteer fire and EMS coordinator. Firefighters responded to the substation at 12:45 p.m., he said, and they put the fire out within an hour.

With the grid damaged, nearby buildings lost power or switched to their backup electrical systems as safety precautions. Once Pepco restored power, customers could switch back to their main systems.

Pepco crews and system engineers are further investigating the incident’s cause, Kelly said. On this campus, Baker said there are no additional problems related to the outage they are aware of.

2:45 p.m. Buildings across the campus lost power Tuesday afternoon after a major regional power outage, PEPCO and facilities management officials said.

At about 12:45 p.m. today, lights shut off in buildings such as Stamp Student Union and the University Health Center.

The blackout was campuswide, said Facilities Management Executive Director Bill Olen, but students on Twitter reported some buildings, such as South Campus Commons, still had power.

The university closed at 2 p.m. due to the outage, university President Wallace Loh announced.

University Police spokeswoman Sgt. Rosanne Hoaas said police are setting up a command center in the operations room to coordinate with representatives from fire departments, police officers and people around the campus to continue to gather more information.

“We have received calls of people stuck in elevators on campus and fire [departments] have been responding out there to get those individuals out of the elevators,” Hoaas said. “We’ve had no reports of injuries at this time.”

As of 1:15 p.m., PEPCO officials said they are “gathering data” on the outage. Shortly after the blackout began, officials said they did not know when power would return.

There are three outages near the campus, according to the PEPCO online outage map. The closest one, on Route 1, is expected to have power restored by 10 a.m. tomorrow. The cause of all nearby outages is listed as “under evaluation.”

Downtown Washington was also affected by the outage, including the White House, Justice Department, State Department and Smithsonian museums, according to The Washington Post.

Hoaas also advised the campus community not to use elevators and to instead use stairwells, and she said to make sure all phones are charged to its conserve power until electricity is restored.

CORRECTION: Due to a reporting error, a previous version of this story incorrectly stated the power was out for five hours. The power was out for four hours. This article has been updated.