An emergency worker inspects a car after it failed to stop at an intersection and crashed due to the Los Angeles power blackout. (Reuters)

Los Angeles, Sept. 13: A blackout caused when maintenance workers inadvertently cut a power line rolled through large parts of Los Angeles yesterday, stranding people in elevators, tangling traffic, and prompting the evacuation of some high-rises and other structures.

Officials said about half of this far-flung city, served by the Los Angeles Department of Water and Power, the largest public utility in the nation, lost power starting at 1 pm. Power was restored two hours later. Los Angeles International Airport lost its lights, but its generator kicked in, and a spokesman said no flights were delayed.

A spokeswoman for the utility said workers at a receiving station mistakenly cut one line and then hooked up the wrong wires, causing a power surge into a line that was not expecting that much electricity.

“Something was cut,” said Gale Harris, a spokeswoman for the Department of Water and Power, which also lost power during the blackout. “Somebody said: ‘Whoops.”

Stranded on the street, some people expressed fears that the blackout was part of a terrorist attack. Yesterday’s power loss came a day after ABC News, on the fourth anniversary of the September 11, 2001, attacks, aired a videotape of a purported al Qaida member threatening attacks against Los Angeles and Melbourne.

The Los Angeles Police Department went on “full tactical alert,” and officers were not allowed to leave work after their shifts ended. The Los Angeles office of the Internal Revenue Service closed after a computer glitch occurred when power was restored.

“Our most significant calls related to this power outage have just been stuck elevators,” said spokesman Ron Myers. “We’re just urging people to stay put.”

Long lunch breaks turned into a short workday, as thousands of workers headed home early, jamming roads already snarled with traffic.

At Grauman's Chinese Theatre in Hollywood, one of the city’s landmarks, the power went out for about seven minutes, interrupting a comedy called The Man.

“Imagine if the power had cut out when we were showing The War of the Worlds,” quipped usher Lauren Fisher.

Some, remembering the collapse of the World Trade Center towers, abandoned their high-rise offices despite assurances from security personnel that they should remain at their desks. “When they said to stay, I thought: ‘I’m going,’” clerical worker Erica Fernandez said.