Council leaders have paid tribute to the "iconic" Queen Elizabeth's "extraordinary devotion" following the monarch's death, aged 96.
Cllr Beaty Bainbridge, chair of Durham County Council, said: "We are greatly saddened to hear of the passing of Her Majesty The Queen. Our thoughts are with the Royal Family at this sad time.
"As Britain's longest-serving monarch, the Queen demonstrated extraordinary devotion to her duties and to the people she served.
"She was an important figurehead for the UK during a reign of more than 70 years, which saw unprecedented changes to our country and way of life.
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"The Queen travelled more widely than any other monarch and this included many visits to County Durham.
"I am sure that all those who met her, whether in the early years of her time on the throne or more recently, will have fond memories of her visit.
"As a mark of respect, flags at County Hall and our other civic buildings in Crook and Spennymoor are being flown at half-mast.
"We know that people in County Durham will want to express their condolences and we will provide information on how to do so in due course."
A statement from Durham County Council shortly after the news stated: "We have officially received the sad news of the passing of Her Majesty The Queen.
"Arrangements are currently being made for remembrance services and we will update you with further details as soon as we have confirmation of them."
Read more: Queen dies - Book of condolence for Her Majesty
Darlington Borough Council leader Jonathan Dulston said: “Along with so many millions of people around the world, I feel tremendous sadness and shock at the passing of our beloved monarch, Queen Elizabeth II.
"On behalf of my fellow councillors, colleagues and the people of Darlington, I send our heartfelt condolences to the entire Royal Family.
“Having enjoyed such a long and happy reign, there will be very few people around today who can remember a time when Her Majesty was not our sovereign, and the loss of such an iconic leader will be felt very deeply, not just in Britain but across the Commonwealth and around the world.
“Her Majesty made several visits to Darlington over the years, particularly in 1967 when she and the Duke of Edinburgh commemorated the 100th anniversary of the town being given a royal charter by Queen Victoria. The royal couple also visited Darlington in 2002, as part of the Queen’s golden jubilee tour.
“Her Majesty has been a defining figure at the heart of our national consciousness for decades. Her place in history is assured and her contribution to public life in this country will never, ever be forgotten.”
Read more: Queen dies - North East pays tribute to Elizabeth II
He told the Local Democracy Reporting Service: "Absolutely heartbroken to learn of the loss of Her Majesty The Queen.
"An absolutely dedicated public servant for as long as I've been alive. I'm just speechless, I suppose.
"She's been the one consistent person in all of our lives and to know that she's no longer here is quite daunting.
"She's provided stability, probably even more poignant at this time because that's probably what the country's looking for. It's a really, really sad day."
He said arrangements would be made for a condolence book to be set up and for people to lay flowers.
He added the Darlington R & B Festival, which was due to run this weekend, would be cancelled.
Councillor Anne-Marie Curry, Mayor of Darlington, said: “I was greatly saddened to hear the news of the passing of Her Majesty the Queen.
"My thoughts and those of my family are with the new King Charles III, the Queen Consort and the wider Royal Family at this sad time.
“It will take some time for us all to process this loss, as while very few of us had the opportunity to meet Her Majesty in person, she touched all of our lives in one way or another over the years.
"We will always remember her enormous contribution to our country.”
Councillor Kevin Nicholson, Darlington Borough Council's cabinet member for health and housing, tweeted shortly after the news broke: "Look after her Philip, she's yours to protect now, I'm actually devastated.
"I just can't imagine a world without the Queen."
Read next:
- Queen dies: Updates as Buckingham Palace announces death of monarch
- Queen Elizabeth II: A life in pictures
- Queen Elizabeth II dies: 50 pictures of The Queen in the North East
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