Arnold said in a social media video in May that he had been diagnosed with advanced-stage clear cell renal carcinoma that had spread to one of his lungs. 3 Doors Down cancelled their planned 2025 summer tour because of his illness.
3 Doors Down, formed in 1996 in Escatawpa, Mississippi, rose to popularity in 2000 with the Arnold-penned single Kryptonite, which peaked at No 3 on the Billboard Hot 100.
Other hits included When I'm Gone and Here Without You, both top-five singles on the Billboard Hot 100. The band has been described as post-grunge, alternative rock and hard rock.
"As a founding member, vocalist and original drummer of 3 Doors Down, Brad helped redefine mainstream rock music, blending post-grunge accessibility with emotionally direct songwriting and lyrical themes that resonated with everyday listeners," the band said in a statement posted on its official Instagram account.
Arnold died peacefully surrounded by loved ones including his wife Jennifer, according to the statement.
"Above all, he was a devoted husband to Jennifer, and his kindness, humour and generosity touched everyone fortunate enough to know him," the band's statement said.
"Those closest to him will remember not only his talent, but his warmth, humility, faith and deep love for his family and friends."
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