Jack Russell, the iconic frontman of Los Angeles hard-rock band Great White, died on Thursday at age 63. The singer’s family announced his death via posts on social media, saying he passed away peacefully with loved ones at his side.

Russell had battled multiple system atrophy and Lewy body dementia, announcing the diagnosis when he retired from touring about a month ago. “I am unable to perform at the level I desire and at the level you deserve,” Russell said in social media posts on July 17. “Words cannot express my gratitude for the many years of memories, love and support. Thank you for letting me live my dreams.”

Russell’s family paid tribute to the famed rock veteran with Thursday posts on his Instagram and Facebook pages that said:

“With tremendous sadness, we announce the loss of our beloved Jack Patrick Russell — father, husband, cousin, uncle, and friend. Jack passed peacefully in the presence of his wife Heather Ann Russell, son Matthew Hucko, cousin Naomi Breshears Barbor, and dear friends Billy and Cheryl Pawelcik. Details of a public memorial will be announced at a later date. Jack is loved and remembered for his sense of humor, exceptional zest for life, and unshakeable contribution to rock and roll where his legacy will forever thrive. His family asks for privacy at this time.”

Russell had released a memoir this summer, “The True Tale of Mista Bone: A Rock & Roll Narrative,” written with K.L. Doty.

Russell, a California native, was the voice and face of Great White, founded in 1977 Los Angeles with guitarist Mark Kendall. The band had several albums and singles to its credit, but earned its greatest fame with the 1987 album “Once Bitten” and a 1989 follow-up, ” … Twice Shy.” Singles such as “Once Bitten, Twice Shy,” “Rock Me” and “House of Broken Love” were radio mainstays during the ‘80s, and Great White’s videos were in heavy rotation on MTV during the band’s heyday.

“Even though Russell came up in an era filled with great hard-rock singers, his bluesy feel set him apart,” Matt Wake of AL.com said in a recent feature story. “Great White’s best known for their hit 1989 makeover of Ian Hunter’s glam classic ‘Once Bitten, Twice Shy.’ Powered by Russell’s lemon-squeezing vocal — along with Micheal Lardie’s piano, Mark Kendall’s hot guitar and a swaggering groove by drummer Audie Desbrow and bassist Tony Montana — Great White’s version smokes the original.

“But what set Russell apart from many of his fellow frontmen was his ability to elevate a rock ballad with not only range but warmth and nuance,” Wake said. “See his vocals on Great White cuts like ‘House of Broken Love,’ ‘The Angel Song’ and ‘Save Your Love.’”

READ: Iconic ‘80s rock singer looks back: ‘It’s not gonna last forever’

Russell had a solo career, as well, releasing a couple of solo albums in the late ‘90s and early 2000′s. He split with Great White for a time, then returned to the group and participated in a few more reunions through 2009. Russell also toured under the name Jack Russell’s Great White.

In an interview with Wake — originally planned for 2023 with Metal Edge but later published by AL.com — Russell talked about his roots as a rock singer.

“My first band that I really ever got into and put me on a path of music was The Beatles,” Russell said. “My parents bought me the ‘Help!’ album for my sixth birthday. And it just stunned me. I listened to it and was like, this is what I want to do for a living. I mean, I had like a vision — no kidding, a serious vision of what my life was going to be like as a rock star. And everything came exactly the way it was laid out to me. It was really, really strange.

“But I discovered bands like Zeppelin, Aerosmith, Black Sabbath and Deep Purple and all the bands of the ‘70s and I really found a home there,” Russell continued. “I wanted to do that, what these people were doing, so I just kept doing it and doing it and doing it and doing it. Started my own band when I was 11 and these guys are like 16 and stuff. Later on that evolved into another band and eventually I left that band ended up being in an original band with Mark [Kendall] and the rest is history. Those were some good days.”

Russell told Wake he regarded his vocal abilities as “a gift God has given me.” The singer added that, after more than 40 years in the music business, he wasn’t inclined to take his talent for granted.

“Who knows when it’s going to be gone?” Russell said. “It’ll be gone one of these days. I’m starting to feel my age a little bit, but so far so good. Where doing what we can with what we have. You know, I still love it. I’ll be completely devastated when it’s gone. But I have a lot of memories, you know?”

Fans mourned Russell’s death and shared thoughts about his music via Thursday’s Facebook post, which had more than 7,500 reactions and more than 1,500 comments by midnight. Here’s a sampling:

“So terribly sorry to hear this. I remember playing a function as a professional guitarist that Jack was at as a guest.. On a break Jack and I talked in length. I was blown away how nice of a person he was. Besides his tremendous talent. Sending condolences to his family and friends as well as all his fans. Rest in peace Jack. A career to be proud of for sure.” — Vince Mendoza

“LOVE Great White and Jack what an incredible singer thank you so much for the memories and Great White music RIP.” — Bryan E Fichter

“RIP Jack! Great White has been my favorite band since I was 3 years old and will always hold a special place in my heart! Jack was so talented and I was lucky to see him in concert in September of 2018 at TLA in Philadelphia. My thoughts and prayers go out to his family and friends!” — Kraig Hoffmann

“I had the opportunity to see Great White live on several occasions over the years. Jack was an amazing entertainer, vocalist and songwriter. I believe he was one of the best singers of our time. He was a rare talent and will be greatly missed. He certainly leaves an ‘Afterglow.’” — David Baker

“Jack was a helluva Singer and an even better man. Rest in peace brother.” — Cheri Loope Spinazzola

“It makes me so sad to hear this terrible news. I have loved Great White for so long … Jack was most definitely a major icon of the 80s Hollywood Metal scene, with his incredible, unmistakable vocals and musical talent. God bless you, and may you rest in peace Jack Russell … You will be sorely missed.” — Jon Foshee

“I am beyond sad and deeply gutted. RIP Captain Jack, I have loved your voice since I was 14 years old. Rock and Roll has truly lost one of the greatest my condolences to the family and band.” — Jessica Cuddeford

“One of the best voices within our lifetime. Godspeed, Jack. Your music will forever live in my heart.” — Kara Elizabeth Bush

“Heartbreaking!!!! He was a genuinely kind guy, and his music a constant in my life. Meeting him in the ‘90s was a highlight of my life. He gave me a genuine hug and thanked ME as I was thanking him. He meant it. From his heart and soul. He will be missed forever. His voice will live on in me and all of us.” — Diana LD Juarez