Author and Nobel laureate Toni Morrison died on Monday night at the age of 88, her publisher Alfred Knopf said in a statement.

“We are profoundly sad to report that Toni Morrison has died at the age of eighty-eight,” the publisher tweeted. “We die. That may be the meaning of life. But we do language. That may be the measure of our lives.” Knopf did not say how the writer died.

Morrison won the Pulitzer Prize in 1988 and the Nobel Prize for Literature in 1993. She was the first African-American woman to receive the Nobel Prize. In 2014, she was awarded the Presidential Medal of Freedom.

Her most famous work, Beloved, was about the life of a woman African-American slave. Some of her other famous works include Song of Solomon, The Bluest Eye, Tar Baby, Jazz and A Mercy. Morrison wrote 11 novels, five children’s books, two plays, a song cycle and an opera.

“Toni Morrison’s working life was spent in the service of literature: writing books, reading books, editing books, teaching books,” Knopf Editor-in-Chief Sonny Mehta said. “I can think of few writers in American letters who wrote with more humanity or with more love for language than Toni. Her narratives and mesmerizing prose have made an indelible mark on our culture. Her novels command and demand our attention. They are canonical works, and more importantly, they are books that remain beloved by readers.”