This is an NBC News special report. Here's Lester Holt.

And good day, everyone. We're coming on the air with some sad breaking news. Queen Elizabeth

II, Britain's longest reigning monarch, has died at the age of 96. The queen reigned

for seven decades, working with many prime ministers through periods of peace and crisis,

and she took the throne. Her family rushing to be by her side today, after doctors became

concerned for her health. Her death comes after the passing of her husband, Prince Philip

last year. And her passing sets the stage for Prince Charles to become King, Britain's

first new monarch in 70 years. Let's go now to NBC, Senior International Correspondent

Kira Simmons. He's outside Buckingham Palace, Kira.

Well, Lester, you know that this moment is coming, but nothing really prepares you for

it. It does it. It's really stunning. One statement here, I'm just looking down from the

Royal family. The queen died peacefully at Balmoral this afternoon. The King and Queen

consort will remain at Balmoral this evening, and will return to London tomorrow. The King

and Queen consort. So this is the moment when we say in history, the Queen is dead, long

live the King. And the moment that we heard this news behind me at Buckingham Palace,

the flag was lowered to half staff. And I can tell you that millions of people across

this country and around the world will be hearing this news and will be frankly devastated.

The Queen, 96, 70 years as Queen, 70 years of service, an extraordinary life, Lester,

which is incredibly difficult simply to put into words. That is the public side, and

then there is the private side. There is the Queen's children and grandchildren. Through

the day, we have been watching her children race to be with her, a very moving photograph

of Prince William driving a car with two of his uncles and an aunt in the car with them,

...