Harper Lee, 'To Kill a Mockingbird' author, dies at age 89

LOS ANGELES (KABC) -- Harper Lee, author of the iconic novel "To Kill a Mockingbird," has died. She was 89.

HarperCollins spokeswoman Tina Andreadis confirmed the author's death to ABC News on Friday, saying Lee died peacefully on Thursday night.

The mayor's office of her hometown in Alabama also confirmed her death.

Lee, a native of Monroeville, Alabama, published her first book in 1960 and to immediate fanfare. She won the Pulitzer Prize and the work quickly became a literary and popular favorite.

"To Kill a Mockingbird" follows the story of a girl nicknamed Scout growing up in a Depression-era Southern town. A black man has been wrongly accused of raping a white woman, and Scout's father, the resolute lawyer Atticus Finch, defends him despite threats and the scorn of many.

As the civil rights movement grew, the novel inspired a generation of young lawyers, was assigned in high schools all over the country and was a popular choice for citywide, or nationwide, reading programs.

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By 2015, its sales were reported by HarperCollins to be more than 40 million worldwide, making it one of the most widely read American novels of the 20th century.

Lee was awarded the Presidential Medal of Freedom by President George W. Bush in 2007.

The author said for years that she would never write another book, but the manuscript for a second novel, "Go Set A Watchman," was published in 2015.

Despite unenthusiastic reviews and questions whether Lee was well enough to approve the publication, "Watchman" jumped to the top of best-seller lists within a day of its announcement and remained there for months.

Nelle Harper Lee was known to family and friends as Nelle (pronounced Nell) - the name of a relative, Ellen, spelled backward.

Like Atticus Finch, her father was a lawyer and state legislator. One of her childhood friends was Truman Capote, who lived with relatives next door to the Lees for several years.

The Associated Press and ABC News contributed to this report.