A rare palace announcement about Queen Elizabeth II’s health at 12:32 pm (1132 GMT) on Thursday prompted a dash to her country estate in Scotland by close members of the 96-year-old’s family.
A second statement at 6:30 pm announced her death.
Here is the day’s timeline:
Around noon (1100 GMT)
Senior minister Nadhim Zahawi slips into the House of Commons, shortly after new Prime Minister Liz Truss finishes her first major policy announcement outlining a freeze on energy prices. Keir Starmer, leader of the opposition Labour party, is on his feet responding to the announcement.
Zahawi sits next to Truss and hands her a note, sending ripples around the chamber. Starmer is handed his own note and both leaders leave.
Buckingham Palace releases its statement.
“Following further evaluation this morning, the Queen’s doctors are concerned for Her Majesty’s health and have recommended she remain under medical supervision,” it says.
“The Queen remains comfortable and at Balmoral.”
Commons speaker Lindsay Hoyle interrupts debate on the energy plan to relay the development to members of parliament, sending the House’s prayers to the royal family.
Truss says: “The whole country will be deeply concerned by the news from Buckingham Palace this lunch-time.”
The BBC interrupts scheduled programming with the announcement and launches rolling news coverage of developments.
Presenter Huw Edwards appears dressed in a dark suit, white shirt and black tie, in line with the BBC’s dress code for when a member of the royal family dies.
Just before 1:00 pm
The queen’s heir Charles, the Prince of Wales, and his wife Camilla have travelled to Balmoral, aides say.
Around 1:15 pm
The queen’s grandson Prince William, who is second in line to the throne after Charles, is also travelling to Scotland to be with his grandmother, the Duke of Cambridge’s office says.
Around 1.35 pm
Princess Anne is at Balmoral, and Prince Andrew, Prince Edward and his wife Sophie are on the way to Scotland, the domestic Press Association (PA) news agency says of the queen’s three younger children.
A spokesman for Prince Harry, Charles’s second son, and his wife Meghan says the US-based couple will be travelling to Scotland after breaking off engagements on a rare trip home.
But in the end, only Harry makes the trip.
Around 4:00 pm
Princes Andrew and Edward, Sophie and Prince William arrive by plane in Aberdeen for the road journey to Balmoral.
People begin to gather outside Buckingham Palace in London, despite rain.
A car carrying a grim-faced Andrew, Edward, Sophie and with William at the wheel sweeps through the gates of Balmoral.
Buckingham Palace announces: “The Queen died peacefully at Balmoral this afternoon.”
“The King (Charles) and The Queen Consort (Camilla) will remain at Balmoral this evening and will return to London tomorrow.”
Foreign tributes begin to pour in including from US President Joe Biden’s White House, Europe and the Commonwealth, which was headed by the late queen.
Britain’s new Prime Minister, Liz Truss, who was only appointed on Tuesday in one of the queen’s last official acts, is expected to speak shortly.