The music world is in mourning.

Steve Harwell, former lead singer of rock band Smash Mouth, has died following a lengthy health battle. He was 56. A specific cause of death was not revealed.

"Steve Harwell passed away this morning September 4, 2023 at his home in Boise Idaho," his rep Robert Hayes said in a statement obtained by E! News. "He was surrounded by family and friends and passed peacefully and comfortably."

The news comes one day after Hayes had confirmed to E! News that Harwell was in hospice care at home. The musician is preceded in death by his and Michelle Laroque's son Presley Scott Harwell, who died at age 6 months of complications from acute lymphocytic leukemia in 2001.

Harwell co-founded Smash Mouth in San Jose, Calif. in 1994. Throughout the next few years, the group rose to international fame with hits such as "Walkin' on the Sun," "All Star" and a cover of The Monkees' 1966 song "I'm a Believer," which was written by Neil Diamond. The latter two tracks were featured in the animated 2001 movie Shrek.

In addition to his music career, Harwell also made a cameo in the 2001 comedy film Rat Race and starred on the VHI reality show The Surreal Life in 2006.

Harwell retired in October 2021 to focus on his health after exhibiting concerning behavior, such as slurring his words, while performing with Smash Mouth in Bethel, New York.

The band's rep told the Los Angeles Times at the time that the singer left Smash Mouth to focus on longstanding medical issues. A rep for the group told the newspaper that Harwell "has suffered profusely over the years with several types of addiction leading to medical and mental health issues," including cardiomyopathy and Wernickes encephalopathy, a neurological condition that "has greatly impacted his motor functions including speech and impaired memory."

Harwell added in his own statement at the time, "Ever since I was a kid, I dreamed of being a Rockstar performing in front of sold-out arenas and have been so fortunate to live out that dream. To my bandmates, it's been an honor performing with you all these years and I can't think of anyone else I would have rather gone on this wild journey with."

He continued, "To our loyal and amazing fans, thank you, all of this was possible because of you. I've tried so hard to power through my physical and mental health issues, and to play in front of you one last time, but I just wasn't able to. I am so grateful to each and every one of you who has helped Smash Mouth sell over 10 million albums worldwide, put us on top of radio charts and those who have kept All Star relevant as one of the top memes on the internet today."

Following Harwell's retirement, Zach Goode was made the new frontman of Smash Mouth. Goode will continue to tour with band, Hayes confirmed in the statement following Harwell's passing. And the rep noted that Harwell's legacy will live on.

"With Steve, Smash Mouth has sold over 10 Million albums worldwide-wide and topped the charts with two #1 hit singles, five Top 40 singles, three Hot 100 singles, four Billboard 200 albums and a Grammy nomination not to mention the hundreds of film and television placements and of course those musical features in Shrek!" Hayes said in the statement obtained by E! News. "Steve's iconic voice is one of the most recognizable voices from his generation. He loved the fans and loved to perform."

Calling Harwell a "true American Original," Hayes said the recording artist was, "A larger than life character who shot up into the sky like a Roman candle."

"Steve should be remembered for his unwavering focus and impassioned determination to reach the heights of pop stardom," he added. "And the fact that he achieved this near-impossible goal with very limited musical experience makes his accomplishments all the more remarkable.  His only tools were his irrepressible charm and charisma, his fearlessly reckless ambition, and his king-size cajones. Steve lived a 100% full-throttle life. Burning brightly across the universe before burning out. Good night Heevo Veev. Rest in peace knowing you aimed for the stars, and magically hit your target. He will be greatly missed by those who knew and loved him."

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