Prime minister David Cameron has announced more military resources are being deployed to help deal with the devastation caused by severe flooding in the north of England.
Hundreds of troops are being deployed in Yorkshire and Lancashire after torrential rain over the Christmas period led to severe flooding.
The Environment Agency has issued a series of severe flood warnings following the rain, indicating a "danger to life".
Hundreds of lesser warnings are in place across England, Scotland and Wales.
On Sunday morning, Cameron said the response by the emergency forces so far had been "fantastic".
He added the military were being brought in to help deal with "unprecedented rainfall and river levels that have caused this flood".
Residents in areas such as York are still being evacuated after the River Foss and Ouse burst their banks.
North Yorkshire police advised between 300 and 400 people in York to evacuate their homes near the rivers, The Guardian reported.
Superintendent Dave Hannan said in a statement: "Over the coming hours and days, we will continue to monitor the situation in residential areas that are at risk, and working with local authority partners, will take the necessary action to ensure the safety of local residents."
Greater Manchester, northern Wales and Leeds have also been severely affected.
The River Aire was expected to reach a record height by 11pm on Saturday, causing the Environment Agency to issue a flood warning in the central Leeds Area.
"This severe flood warning has been issued because of significant impacts to infrastructure and risk to life in the area," a statement declared.
Electricity North West said in a statement on Sunday that over 7,500 customers are without power across North West of England.
Operations director Mark Williamson said: "Our engineers have worked through the night and will continue to work today in extremely difficult conditions to restore power to the remaining 7,500 customers in Lancashire and Greater Manchester.
"There are still a number of substations that are flooded and we can't get access, but as soon as the water recedes then we have teams ready to go in and check the damage and make repairs."
Environment secretary Elizabeth Truss said on Sunday that the situation in Yorkshire and Lancashire had been caused by "unprecedented levels of rain and high river levels", the BBC reported.
"We are still in a situation with major flood warnings and we are still working to protect properties and lives," she added.
The northwest of England was already severely affected by flooding after Storm Desmond hit the area earlier this month.
"It is the intensity of this rainfall, on already saturated ground that has sparked the issuing of the Met Office's most severe warning," a spokesperson for the Met Office said. "This is expected to lead to widespread river flooding and surface water flooding."
The rain on Friday and Saturday has caused serious damage in some areas, leaving roads under water in central Leeds, and houses in Mytholmroyd, West Yorkshire and Whalley were evacuated after rivers overflowed, the BBC reported.
Some areas, according to The Guardian, had received about a months-worth of rain in just a few hours.
Many people across Yorkshire were stranded in cars as roads were overwhelmed with flood water.
Flood sirens were sounded in Mytholmroyd in Calderdale, West Yorkshire, as the area was badly hit by torrential downpour.
"This is a very fast moving situation and we have been deploying critical response teams and personnel overnight to where they are most needed," Truss said in a statement.
"The Environment Agency, emergency services and military personnel have sent significant resources overnight to Lancashire and Yorkshire to help protect people, homes and businesses as well as maintaining the response in Cumbria."
"I would like to again pay tribute to the tireless work of front line staff over the last month and the Christmas period, and the extraordinary resilience of the people affected, which I have seen first hand," she added.
"My thoughts and sympathy continue to be with people flooded out of their homes this Christmas and I can assure them we are doing everything we can to help communities recover from these storms."
Hebden Bridge in West Yorkshire saw particularly severe flooding.
Hebden Bridge town centre was almost entirely underwater after the River Calder burst its banks.
Local police reported no injuries but shared images of a town completely submerged by water.
A nearby hostel was said to be offering shelter to anybody who needed a warm, dry place to stay.
Footage from Sky News showed residents of Whalley, Lancashire, in a race against time to leave their homes before the river burst its banks.
One woman praised relief efforts by local police, saying that the area felt much better prepared than when Desmond hit three weeks ago.
"We have been warning people to take action now to make sure that they keep themselves safe, to check out for vulnerable friends and relatives, to move valuable papers and other belongings to a safe place out of the way of water," the Environment Agency's Ben Lukey told BBC Breakfast.
But one Whalley resident told Sky News that she wouldn't let her day be dampened by the events.
"I'll still go out for a couple of drinks tonight!" she added.
Lancashire Fire and Rescue service warned people not to visit areas worst affected by the floods.
"A severe flood warning means danger to life. It doesn't mean 'come and have a look'!
"Please don't come to visit Whalley or Ribchester now," a spokesperson tweeted.
On Christmas morning, army troops were deployed to some of the worst affected areas of Cumbria to help prepare for the arrival of Storm Eva.
"Even at Christmas our Armed Forces are keeping us safe," defence secretary Michael Fallon said in a statement.
"Once again they are responding to the Cumbria floods with a level of commitment that is to be applauded."
Laura Silver is a reporter for BuzzFeed News and is based in London.
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