Harper Lee, the reclusive author whose 1961 novel To Kill a Mockingbird became a national institution and the defining text on the racial troubles of the American deep south, has died at the age of 89.
The news was confirmed by the mayor's office in her hometown of Monroeville, Alabama.
The novelist was born Nelle Harper Lee on 28 April 1926.
In 1960, she published To Kill a Mockingbird, a huge critical and commercial success which won the Pulitzer Prize for fiction. A sequel Go Set a Watchman, was published in 2015.
To Kill a Mockingbird sold more than 40 million copies worldwide.
Michael Morrison, the head of HarperCollins US said in a statement: "The world knows Harper Lee was a brilliant writer, but what many don't know is that she was an extraordinary woman of great joyfulness, humility and kindness.
"She lived her life the way she wanted to - in private - surrounded by books and the people who loved her. I will always cherish the time I spent with her."
Apple CEO Tim Cook tweeted: "Rest in peace, Harper Lee. The one thing that doesn't abide by majority rule is a person's conscience."
Rest in Peace Harper Lee!
"Shoot all the blue jays you want, if you can hit 'em, but remember it's a sin to kill a mockingbird." That was the only time I ever heard Atticus say it was a sin to do something, and I asked Miss Maudie about it. "Your father's right," she said. "Mockingbirds don't do one thing except make music for us to enjoy." - To Kill A Mocking Bird (1961)