LOS ANGELES -- An error by utility workers caused a blackout across major portions of Los Angeles yesterday afternoon, trapping people in elevators and snarling traffic at intersections, authorities said.
About 2 million people were affected by the resulting power surge and outages, which were reported from downtown west to the Pacific Coast and north into the San Fernando Valley.
Much of the power, which failed at about 12:30 p.m., was restored within less about 2 1/2 hours; all power was expected to be restored by 5 p.m.
Workers who were cutting wires mistakenly sliced them as a group rather than individually, causing a short and leading to the trouble, officials said.
''They cut wires that caused circuit breakers to trip," according to Ed Miller, director of power system operations and maintenance for the Los Angeles Department of Water and Power.
Initially, the department said they believed the outage occurred after the cables were incorrectly reconnected.
Downtown high-rises went dark, fire officials said they received reports of people stuck in elevators, and stoplights went out at intersections across the city. Neighboring cities, including Burbank and Glendale, also were affected.
The Police Department went on ''full tactical alert," meaning no officers were allowed to leave work when their shifts were over.
But calm prevailed in downtown Los Angeles, with office workers taking the opportunity for an extended lunch as police and fire sirens echoed in the background.
The blackout came a day after ABC aired a videotape of a purported Al Qaeda member making terrorist threats against Los Angeles and Melbourne on the fourth anniversary of the Sept. 11 attacks.
But even before the utility explained what happened, Homeland Security Department spokesman Russ Knocke said there was no indication of terrorism.
Still, Mayor Antonio Villaraigosa recognized that the timing ''created a heightened sense of concern."
Some Los Angeles neighborhoods did not lose power at all.
Los Angeles International Airport lost power, but its emergency generator kicked in promptly and no flights were affected, said Harold Johnson, an airport spokesman. UCLA Medical Center used backup generators and said that there was no danger to patients.
Los Angeles operates its own power utility, which serves 1.4 million electricity customers. Customers of
Bob's Big Boy restaurant in Burbank lost power for 90 minutes. ''No hamburgers," manager Frank Rodriguez said.