Lincolnshire is in mourning following the sad death of The Duke of Edinburgh aged 99.

A spokesman for the Royal Family commented: "It is with deep sorrow that Her Majesty The Queen announces the death of her beloved husband, His Royal Highness The Prince Philip, Duke of Edinburgh.

"His Royal Highness passed away peacefully this morning at Windsor Castle.

"Further announcements will made in due course.

"The Royal Family join with people around the world in mourning his loss."

After the announcement around 12-noon, South Kesteven District Council said it would be sending its official condolences to Buckingham Palace.

As a mark of respect, council Union Flags are being flown at half-mast until the morning following the Royal Ceremonial Funeral.

The Chairman of South Kesteven District Council, Cllr Breda Rae Griffin said: "It is with much sadness that we have learned of the passing of Prince Philip, the Duke of Edinburgh.

"My sadness at this time is shared with Members and officers of the Council and, I am sure, South Kesteven district residents, as we remember with affection and gratitude the support and service given by His Royal Highness to Her Majesty the Queen.

"Prince Philip has been at the Queen's side throughout her reign and has carried out numerous royal engagements on her behalf. As a district, we have all greatly valued his role, his contributions to national life, and his dutiful dignity."

The Leader of the Council, Cllr Kelham Cooke, said: "On behalf of South Kesteven District Council, I express our condolences to the Royal Family on the passing of His Royal Highness, Prince Philip, the Duke of Edinburgh. His Royal Highness epitomised a life of service and dedication, not only to our Sovereign, but to the armed forces, the voluntary sector, and Britain's young people.

"The Youth Award Scheme in his name goes from strength to strength and continues to provide opportunities for so many. This, coupled with his brave and selfless heroism in the Royal Navy during the war and his active support of many good causes, provides a model of a life well-lived. His Royal Highness has left a lasting legacy of hope and opportunity which will illuminate the lives of future generations to come.

"We are very thankful for His Royal Highness' service and legacy, and he will be long-remembered in the hearts of the people of South Kesteven."

The council has organised its own district online book of condolence at www.tolbc.com/SouthKestevenHRHPP to ensure that it complies with the Government's current Covid restrictions.

The Buckingham Palace online book of condolence is at https://www.royal.uk/

Floral tributes can be laid at the following locations, observing social distancing.

Grantham – St Peter's Hill

Bourne – next to the War Memorial, Well Head, South Street

Signs are in place marking where the flowers should be left.

Leader of Lincolnshire County Council, Cllr Martin Hill, said: "This is an extremely sad time for the entire nation. As the husband and loyal consort of our longest serving Monarch, he provided immense support and presided over numerous public engagements until he stepped down from his duties in 2017.

"We were very fortunate to host him several times over many decades, enabling him to see our county at its best. From visiting the East Coast after the devastating flooding in 1953 to the opening of facilities at Bourne Grammar School in 2013, he has shown support for our communities in Lincolnshire many times.

"As well as public events, privately he visited the county many times – mainly RAF Cranwell to support his grandson, Prince William, who was training to become an RAF pilot.

"Not only did he visit often, his well-recognised 'Duke of Edinburgh' scheme also ran in the county, which made a huge difference in enhancing the lives of many of our young people.

"The Duke was an enigmatic character and will be greatly missed by all who knew him.

Toby Dennis, Lord-Lieutenant of Lincolnshire, said: "Since 6 February 1952, HRH The Duke of Edinburgh has been Her Majesty The Queen's "strength and stay all these years".

Every day of their 73 years of married life Prince Philip has supported Her Majesty in all aspects of our present day Monarchy. President or Patron of over 780 organisations and his legacy of The Duke of Edinburgh Awards scheme demonstrates his public work for which the national is eternally thankful.

"His passing will make us even more willing to serve Her Majesty, her heirs and her successors."

Michael Scott, Lincolnshire's High Sheriff said: "I share the sadness of people across the globe following the passing of HRH The Duke of Edinburgh. We remember with affection and gratitude the lifetime of service he has given as consort to Her Majesty The Queen.

"Before he stepped down from royal duties in 2017, he had attended over 20,000 events and we have been lucky enough to have welcomed him to Lincolnshire on many occasions going back to the 1950s. Whether it was supporting communities hit by devastating floods or the opening of major landmarks, he showed great humility, understanding and interest in our county."

The Union Flag will be flown at half-mast at County Offices, Newland, Lincoln until 8am on the day following the funeral – anticipated to be Saturday 17 April.

Grantham MP Gareth Davies said: It is with great sadness that I heard the news of the death of HRH Prince Philip, the Duke of Edinburgh. My first thoughts are with Her Majesty The Queen, to whom I have written to extend my condolences on the loss of her husband. I know this sorrow is shared by countless others across the Grantham and Stamford constituency, Lincolnshire, the United Kingdom, and the Commonwealth.

"Prince Philip's life was marked by 70 years of tireless public service, including fighting for Britain's freedoms in the Second World War. We are forever grateful for his work to benefit the lives of young people, marked by the Duke of Edinburgh Awards scheme among the many charities and voluntary organisations in which he was involved. We can all learn from his devotion, fortitude, and sense of duty.

"Here in Grantham and Stamford constituency, we have been fortunate to receive visits by Prince Philip to our three main towns. His contribution to the history of Stamford came in 1961 when he and Her Majesty the Queen celebrated the quincentenary of the town by hosting a gala at Burghley House. We were fortunate to welcome Prince Philip to Grantham in 1973 to inspect local schools' Duke of Edinburgh participants, and in 2013 we received him in Bourne where he opened the Turing Centre at Bourne Grammar School.

"Above all else, the Duke was a constant support and trusted counsellor to Her Majesty the Queen as well as a much-loved father, grandfather, and great-grandfather. The whole Royal Family is in our thoughts today as we mourn with them."