Washington, Aug 15: Terrorism sprang to mind when the lights suddenly went out for millions of Americans and Canadians. But fears of al-Qaeda strikes on the vulnerable power grid were unrealized, federal officials quickly determined. Had it been an actual attack, it is unlikely terrorists would have met their goals. There was little evidence of panic, violence or threats to public health and civil order.

Call it a weapon of mass disruption. Air conditioning went out. People were trapped in subways and elevators. Planes were grounded and traffic lights went dark. Cell phones didn't recharge. New York, Cleveland, Toronto and Detroit lost most of their power yesterday afternoon. It is possible a few people died, experts said - perhaps someone had a heart attack on the top of a high-rise and it took too long for paramedics to climb the stairs.

Thanks to backup power supplies - probably last upgraded before Y2K - the vital institutions kept the lights on. Hospitals stayed open and jail doors stayed closed.

The speed and scope of the outage were staggering. Twenty power plants shut down as a safety mechanism and were slowly being reintegrated into the grid. Safeguards prevented it from spreading further. The cause was unclear.

"I think this situation indicates that technology is imperfect and at times will fail," said Brian Roehrkasse, a Homeland Security Department spokesman. "This indicates the importance of having in place protections to guard our critical infrastructure as well as crisis plans for when the infrastructure becomes inoperable." Bureau Report