US struggles after blackout

Cities across the north-eastern United States and Canada restored power to millions of people on Saturday, following the largest blackout in North American history.

Electricity flowed in Cleveland on day two of the blackout, but water moved at a trickle.

The lights returned to Times Square in the centre of Manhattan, but only 10 of the system's 24 main underground lines were running early on Saturday. The lights clicked on in almost two million homes in Michigan, but gas remained in scarce supply around Detroit.

Some customers in the Cleveland area and in New York received the unkindest cut of all: power was restored and then turned off due to rolling blackouts needed to conserve electricity.

Officials in Michigan warned that the whirr of air conditioners and the glow of televisions might not return until the end of the weekend as the cause of the massive outage remained a mystery.

Canada and the United States formed a joint task force to investigate what caused the blackout and how to prevent it from happening again.

The blackout swept across a huge slice of North America, knocking out service in parts of eight states and Canada in just nine seconds.

President George Bush said part of the problem was "an antiquated system" to distribute electricity nationally.

"It's a wake-up call," Bush said. "The grid needs to be modernised, the delivery systems need to be modernised."

In New York City, Mayor Michael Bloomberg said he received a call from Bush offering congratulations on the city's handling of the crisis. Crime there was actually down overnight compared to an average evening, he said.