Jim Ladd, an icon of Los Angeles rock radio, died Sunday. He was 75.

SiriusXM announced the news in an online post Monday.

"SiriusXM remembers Jim Ladd, legendary freeform rock DJ," the company shared on X, formerly known as Twitter. "For over 50 years, he championed classic rock and interviewed many of the greatest artists in his Los Angeles studios and on SiriusXM’s Deep Tracks channel."

Tributes for Ladd poured in on social media, including from Doors drummer John Densmore, who hailed Ladd as "The Last DJ."

"There wasn't a more soulful spinner of music," Densmore wrote on X. "The songs he played were running through his blood, he cared so much for rock n' roll.  Irreplaceable... a very sad day, which can only be handled by carrying his spirit forward."

According to the Los Angeles Times and Deadline, Meg Griffin, a fellow DJ and colleague of Ladd's, announced his death on air on Sirius XM Monday. The outlets report Ladd died from a heart attack.

"He never stopped caring," Griffin said, per the outlets. "He delivered the truth. He lived for the music."

Ladd wrote the book "Radio Waves: Life and Revolution on the Fm Dial" about his storied career, which published in 1991. He received a star on the Hollywood Walk of Fame in 2005.

According to the Los Angeles Times, Ladd inspired the 2002 Tom Petty song "The Last DJ."

Ladd described the song as "a love song about radio" in an interview after its release, per the Los Angeles Times. "Some people totally misinterpreted the song as an attack on radio when it is exactly the opposite," he said.

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