An underground electrical fire in downtown York City burned for more than two hours Monday night, spewing thick black smoke and flames from three manholes.

The fire was reported about 7:30 p.m. at the intersection of South Duke and East King streets.

In order to douse the flames, Met-Ed had to shut off the local power grid in the area, said York City Fire Chief David Michaels.

The fire was extinguished a little before 10 p.m., he said.

"This was a lot of fire on this one," Michaels said. "This fire actually was pretty much about a block long."

No one was hurt, he said.

Met-Ed crews had to wait to go into the underground "vault" to repair the electric lines until high temperatures from the blaze decreased, he said.

York City emergency personnel stand-by as flames and smoke pour from a manhole cover on South Duke Street in front of the Rex/Laural fire station. MORE PHOTOS (John A. Pavoncello)

Outage: A nearly four-block radius around Continental Square, as well as other areas in the city, were in the dark because of the power outage, Michaels said.

At the height of the outage, 830 houses and businesses were without power, according to Met-Ed spokeswoman Kathy Seilhamer.

Power to traffic signals was restored about 12:30 a.m. Tuesday.

As of 9 a.m. Tuesday, 13 customers were still without power, primarily on South Duke Street between Market and King streets, according to Seilhamer. The Salvation Army building was also without power Tuesday morning, she said.

"We're working today to restore power to all the customers," she said, but had no estimate when that would happen.

Michaels said the blaze was started by an accidental electrical malfunction.

"Most likely, something shorted out," he said.

"There was a fault in the underground network," Seilhamer said, but what specifically failed remains undetermined.

Flaming manholes: The underground fire created a great amount of pressure, blowing off at least one manhole cover, Michaels said, and perhaps several.

That posed a substantial risk to residents and emergency crews in the area.

"What it does, it blows the manhole covers up off the streets," Michaels said. "When we got here, we were able to get those manhole covers off to prevent that from happening."

Burning insulation around the wires created thick black smoke that spread to parts of the city. Firefighters were dispatched to a few calls for smoke during the South Duke Street incident, Michaels said.

The underground fire spread from East King Street, south on South Duke Street to East Mason Avenue.

Traffic problems: At times, underground explosions could be heard, and flames shot about 12 feet in the air from the manholes.

After firefighters put out the underground blaze, another issue arose, he said.

"What then became the problem for us was the traffic lights being out," the chief said. "What we did is call in fire police from around the county. ... We did what's called a 'county all-call.' That goes to every fire department in the county."

Dozens of fire police officers from all over York County responded to direct traffic, he said.

'That's scary': The explosions were what attracted the attention of Miguel Rosado, who lives in the 100 block of South Duke Street.

A neighbor told him about the explosions, and he ventured outside to see what was happening.

"It's crazy," Rosado said as he stared at the fire. "That's scary."

No homes in the area were evacuated, Michaels said, but the Salvation Army at 124 S. Duke St. was because smoke blew into its basement.

The organization was holding an event with children in attendance at the time, he said. Salvation Army officials set up its canteen service and provided drinks to firefighters.

- Staff writer Elizabeth Evans contributed to this report. Reach Greg Gross at 505-5434, ggross@yorkdispatch.com, or follow him on Twitter at twitter.com/greggrss.