Mourners are crowding outside Buckingham Palace tonight.

The British people paying their respects and sharing in the loss of their Queen Elizabeth, the second.

Britain's longest serving monarch dead at the age of 96

after 70 extraordinary years on the throne. The palace says she died peacefully

at Balmoral Castle in Scotland, where her closest relatives

are gathered right now, including the new king, Charles III.

He's calling this a moment of the greatest sadness for him and for all members of the royal family.

Welcome to our viewers here in the United States and around the world.

I'm Will Flitzer in the Situation Room with CNN's special live coverage of the death of

Queen Elizabeth. We have extensive live coverage coming up, but there you see the President of the United States.

President Biden, he's at the British embassy right now, paying his respects, he's signing the book of condolences over at the British Embassy here in Washington.

You see him there with the British Ambassador to the United States,

Karen Pierce and the First Lady of the United States,

Dr. Jill Biden, as well.

We're going to monitor what the president is doing

over at the British embassy. We anticipate he will be saying something about Queen

Elizabeth, expressing his condolences, paying his respect to the United Kingdom,

to the British monarchy.

We will have live coverage of that coming up.

But I want to bring in Max Foster right now.

He's over at Buckingham Palace watching all of this history unfold for us.

Max truly, truly significant moments unfolding.

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