Government buildings throughout Washington, including the White House, Capitol complex and State Department, briefly lost power on Tuesday.
Electricity provider Pepco said the outages was caused by an issue with a transformer that began around 1 p.m.
"There was never a loss of permanent supply of electricity to customers. The dip in voltage caused equipment at some customer facilities to transfer to their backup systems," said Pepco spokesman Marcus Beal.
"The momentary outage, occurred because of customer equipment responding to a dip in voltage. Customers should be able to operate their own equipment at this time. There are no current supply problems. We have crews on site investigating the cause," he said.
Beal said Pepco did not have confirmation that the dip had been caused by an explosion at a facility, as had been reported by some news outlets.
The Department of Homeland Security does not suspect the outages to have anything to do with criminal activity or terrorism.
"At this time, there is no indication that this outage is the result of any malicious activity," said a Department of Homeland Security official.
White House press secretary Josh Earnest said President Obama's was unaffected by the outage, adding that the administration "does not currently see a nexus to terrorism or anything like that.”
At the White House, the lights in the lower press area went off for a few seconds before turning on again. Power also went out in other parts of the building, according to White House staff.
"Power outage affecting many parts of the city, and it affected the [White House] complex. We were on a backup generator and now we are back on normal power," a White House spokesman said.
State Department spokeswoman Marie Harf continued speaking with reporters when the power went out during her midday briefing.
The power also went out at buildings on Capitol Hill.
"Power has been restored to all buildings on U.S. Capitol grounds," said a spokesman for the U.S. Capitol Police. "As Pepco attempts to resolve the problem, we are prepared for any further power outages and/or surges may occur."
CNN anchor Wolf Blitzer said the network's Washington studio has lost power intermittently over a half-hour period.
— Jordan Fabian and Timothy Cama contributed.
— Last updated at 2:30 p.m.