Massive power blackouts Thursday hit many US and Canadian cities including New York and Toronto.
US media reported that a fire in a New York power station had sparked the blackouts.
There was "no evidence" that it was caused by terrorism, New York Mayor Michael Bloomberg told CNN.
Following the massive power cut in New York, hundreds of thousands of people poured onto the streets as offices and buildings were emptied, witnesses said.
Many parts of Detroit were reportedly paralyzed by the widespread power outage, said the local power company Detroit Edison.
In Ottawa and Toronto, Canada, the blackouts occurred at about the same time as similar outages in the US cities of New York and Detroit.
(Xinhua News Agency August 15, 2003)