Torrential rain has caused the worst flooding in the eastern United States for decades.
At least 16 people have died. Over 200,000 people have been forced to leave their homes as swollen rivers rose to dangerous levels.
With roads washed out and essential services threatened, the authorities in New Jersey, New York and Pennsylvania declared “disaster emergencies”. In one city, the US coastguard had to use helicopters to rescue up to 70 people stranded on roof tops. In another, students and teachers were evacuated from a day-care centre as a local river burst its banks.