Simmons died at the age of 50 a week after being hospitalized following a heart attack, the family says. Over the years, DMX has battled with substance abuse.
His label Def Jam Recordings released a statement on the artist's passing.
"Def Jam Recordings and the extended Def Jam family of artists, executives and employees are deeply and profoundly saddened by the loss of our brother Earl "DMX" Simmons," the statement read. "DMX was a brilliant artist and an inspiration to millions around the world. His message of triumph over struggle, his search for the light out of darkness, his pursuit of truth and grace brought us closer to our own humanity. Our thoughts and prayers are with his family and all those who loved him and were touched by him. DMX was nothing less than a giant. His legend will live on forever."
DMX's manager Steve Rifkind posted his condolences on Instagram.
Simmons also received an outpouring of support on social media from fellow celebrities.
❌4L!! Rest In Paradise LEGEND!! 🐕🐕 pic.twitter.com/Y0m0DVl5Up— LeBron James (@KingJames) April 9, 2021
DMX. 🕊 His gift meant so much to so many. Sending love to his family.— Halle Berry (@halleberry) April 9, 2021
RIP DMX. I pray for the comfort of your children and loved ones. 🙏🏿💛 pic.twitter.com/WC5LsaL9j8— Viola Davis (@violadavis) April 9, 2021
DMX and Aaliyah tweets also surfaced as they were close after their roles in the film "Romeo Must Die." DMX and Aaliyah teamed up for the film's soundtrack song "Come Back in One Piece."
In 2001, Aaliyah died in a tragic plane crash in the Bahamas.
"Earl you had and still have a heart of gold. You and Baby Girl will meet again with all the beautiful people we have lost. Will never forget your kindness. NEVER! Blessing to your family! Eternally!" said Diane Haughton, the mother of the late singer Aaliyah, said on Instagram.
DMX made a splash in rap music in 1998 with his first studio album "It's Dark and Hell is Hot," which debuted No. 1 on the Billboard 200 chart. The multiplatinum selling album was anchored by several hits including "Ruff Ryders' Anthem," "Get At Me Dog" and "Stop Being Greedy."
The rapper had four other chart-topping albums including "...And Then There Was X," "Flesh of My Flesh, Blood of My Blood," "The Great Depression" and "Grand Champ." He has released seven albums and earned three Grammy nominations.
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His last album, "Undisputed," was released in 2012.
The Associated Press contributed to this report.