The US city of Houston is in the grip of the biggest storm in the history of the state of Texas, officials say.
A record 30in of rain (75cm) has fallen on the city in the wake of Hurricane Harvey, turning roads into rivers.
The area is expected to have received a year’s rainfall within a week. Five people are reported dead. Helicopters have plucked victims from rooftops.
With rescue services overstretched as the rain continues, many people are having to fend for themselves.
Harvey made landfall as a category-four hurricane late on Friday. It was later downgraded to a tropical storm.
Up to 2,000 people have been rescued in and around Houston, the fourth-largest city in the US, where about 6.6m people live in the metropolitan area.
An inundated care home in Dickinson, about 30 miles (50 km) south east of the city, has now been evacuated by helicopter after an image of several elderly women sitting in a lounge in waist-deep water
went viral on social media.
The US National Weather Service (NWS) says conditions are “unprecedented”. A “flash flood emergency” is in force across the Houston area, with travel near impossible.
Thousands of homes are without electricity. Many schools are closed – as are the two main airports, with runways completely flooded.
A city in crisis – James Cook, BBC News, Houston
Entire suburbs are under water, shops and businesses are shut and, with the motorways around the city cut off and both airports closed, travel is all but impossible.
A marooned hospital has been evacuated while, above the city, engineers are starting an emergency release of water from two bulging dams.
They are warning families who live beside one of the dams to prepare for flooding within hours.
Some residents have been critical of the preparations for this storm, which intensified rapidly in the Gulf of Mexico last week.
In at least one neighbourhood facing severe flooding, people are angry that they were told to stay put only to realise, as night fell, that the waters were rising fast and they could not get out.
The authorities are being stretched to breaking point. It is difficult to see how they could accommodate President Donald Trump, who plans to visit Texas on Tuesday.
If he does decide to travel here, he will find a powerful oil city on its knees.