Rescuers along the hurricane-ravaged Gulf Coast pushed aside the dead to reach the living in a race against time and rising waters, while New Orleans sank deeper into crisis and Louisiana’s governor ordered storm refugees out of this drowning city.

The biggest power cut in American history rolled across a vast swath of the northern United States and southern Canada yesterday, driving millions of people outdoors into stifling rush hour streets – then darkness.

More than 20 people have been injured in a rollercoaster accident at a New England amusement park.