Mary Wilson, the legendary singer and founding member of The Supremes, has died. She was 76.

Wilson died suddenly and unexpectedly on Monday evening, according to a statement to ET from her longtime friend and publicist, Jay Schwartz.

Wilson died at her home in Henderson, Nevada. No cause of death has yet been released.

Wilson is best known for her work with the iconic Motown singing group The Supremes — alongside Diana Ross and the late Florence Ballard — who became one of the biggest musical acts of the 1960s, and created over a dozen No. 1 singles.

Some of the group’s biggest hits include “Where Did Our Love Go”, “Baby Love”, “Come See About Me”, “Stop! In the Name of Love” and “Back in My Arms Again,” among countless other timeless classics.

Last month marked the 60th anniversary of The Supremes signing with Motown Records, and a celebration of the group’s iconic legacy was set to take place throughout the year.

Wilson’s rep told ET that she’d been “working on new music and was set to release a new album this spring.”

She released a YouTube video on Saturday, in which she talked about working on new music, as well as The Supremes’ anniversary.

Aside from her indelible music career, Wilson was also known for her work as a motivational speaker, an advocate for social change and a cultural ambassador for the United States.

Berry Gordy, the founder of Motown, paid tribute to Wilson following the news of her death.

“I was extremely shocked and saddened to hear of the passing of a major member of the Motown family, Mary Wilson of the Supremes,” Gordy said in a statement. “The Supremes were always known as the “sweethearts of Motown.”  Mary, along with Diana Ross and Florence Ballard, came to Motown in the early 1960’s.  After an unprecedented string of number one hits, television and nightclub bookings, they opened doors for themselves, the other Motown acts, and many, many others.”

“I was always proud of Mary. She was quite a star in her own right and over the years continued to work hard to boost the legacy of the Supremes,” he continued. “Mary Wilson was extremely special to me. She was a trailblazer, a diva and will be deeply missed.”

Gladys Knight then told ET in a statement: “She was my girl. She was soft-hearted and loving and always trying to make it work regardless of anything that was happening personally.

“Mary was amazing and when their voices came together she helped them blend, I loved all of them. She was always kind and knew her own strength vocally and personally, she brought something wonderful to The Supremes.

“She sung her part and didn’t need to be upfront, the warmth in her voice and music came from her soul. Back then there weren’t a lot of places for African Americans to be and Mary made it work for her group and that was good for all of us. She was a good friend and I will miss her smile, her voice and her heart.”

Wilson is survived by her daughter Turkessa, her son, Pedro Antonio Jr., as well as 10 grandchildren and one great-granddaughter.

Due to COVID-19 restrictions, services will be private and the family is planning to hold a celebration of her life later this year.

Stars, including Wilson’s fellow The Supremes band member Diana Ross, took to Twitter to pay tribute to the beloved musician.

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