Harper Lee, the celebrated author of To Kill A Mockingbird, has died aged 89.

The Mayor's Office of Monroeville, Alabama, confirmed the news to the Press Association.

Publisher Penguin Random House also posted a message on Twitter saying “Rest in peace, Harper Lee.”

Lee was born in Monroeville in 1926, the youngest of four children. She studied at the University of Alabama from 1945 to 1949 before moving to New York, where she began writing fiction in her spare time. Lee eventually signed with an agent in 1956. 

To Kill a Mockingbird is regarded as an American literary classic, selling 40 million copies worldwide. 

Her second book, Go Set a Watchman, was written in the mid-1950s and released last year. Despite the global success of her book and the awards, honours and accolades bestowed upon her after its release, Lee lived a quiet life, was reticent to speak to the press and refused all requests for interviews. The decision to publish her second book was shrouded in controversy.

She traveled between New York and Monroeville for much of her life, where she lived with her sister Alice, and gave very little information away about her private life. 

Her cousin Richard Williams, who ran a drug store once in Monroeville, once said: “I asked her one time why she never wrote another book. She told me, 'When you have a hit like that, you can't go anywhere but down'. ”