Legendary music producer Frankie Knuckles has passed away at the age of 59.
Knuckles, who became known as the Godfather of House, was a pioneer of the house music movement in the '80s in New York City and Chicago.
Knuckles' first break as a solo artist was in 1991 when Virgin released his debut album, Beyond the Mix—which featured several major hits like "The Whistle Song" and "Rainfalls."
In 2004, Chicago renamed a portion of Jefferson Street, near the site of the original Warehouse club where he played regularly, as Frankie Knuckles Way.
"I am devastated to write that my dear friend Frankie Knuckles has passed away today. Can't write any more than this at the moment. I'm sorry," Morales said on Twitter.
He also added on Facebook, "My brother my friend my mentor my king. Where do we go from here?" with a photo of him hugging his longtime confidant.
The Roots' Questlove Jenkins wrote on his social media account, "Jesus man. Frankie Knuckles was so under-appreciated. He was the dj that dj's aspired to be. True dance pioneer."
Knuckles, who was born Francis Nicholls, was born in the Bronx in 1955. At this time, the official cause of death is unknown.