After he took the stage before a roaring sold-out crowd at Xcel Energy Center in June, Tom Petty promised "100 percent rock 'n' roll, no artificial sweeteners." That's exactly what he delivered that night and throughout a tenaciously enduring 40-year career with his rock-steady band, the Heartbreakers.

Twin Cities fans who saw Petty happily and heartily roll through a two-hour set just four months ago were among those most shocked and heartbroken to hear the Rock and Roll Hall of Fame legend, 66, died Monday following a heart attack.

Celebrity news site TMZ first reported that Petty's wife, Dana York, found him unconscious in their Malibu home and called 911 around 10:45 p.m. Sunday. CBS erroneously reported that he had died.

The Gainesville, Fla., native reportedly was not breathing and had no brain activity when he was brought to UCLA Santa Monica Hospital. His death was widely reported but then retracted Monday afternoon, as he reportedly lingered on life support.

He was officially pronounced dead Monday night after Tony Dimitriades, his longtime manager, released a statement saying Petty "died peacefully at 8:40 p.m. PT surrounded by family, his bandmates and friends."

Known for such ubiquitous and anthemic radio hits as "Free Fallin'," "American Girl" and his would-be theme song "I Won't Back Down," Petty fought with corporate record companies, battled addictions and stuck to hardworking tour schedules over the decades to become one of rock's most independent forces and revered songwriters.

He racked up 13 gold- or platinum-selling records going back to his 1976 eponymous debut with the Heartbreakers, which included the singles "Breakdown" and "American Girl." He made the leap to arena-level status with 1979's "Damn the Torpedoes," featuring "Refugee," "Don't Do Me Like That" and "Here Comes My Girl."

With success came his first in a series of many disputes with former record label MCA. When the company wanted to charge $9.98 for the follow-up LP to "Torpedoes," Petty threatened to title the record "$8.98." It came out as "Hard Promises" instead — with an $8.98 list price.

Petty's biggest album was the 1989 solo effort "Full Moon Fever," which introduced him to a new generation of fans via "Free Fallin' " and other hit songs such as "Running Down a Dream." He also became an unlikely star of the early-MTV era with his "Alice in Wonderland"-themed 1983 video "Don't Come Around Here No More." The hits kept coming into the '90s with "Learning to Fly," "Mary Jane's Last Dance" and "You Don't Know How It Feels."

Also known as a great collaborator, Petty helped produce and/or record albums by some of his heroes, including Johnny Cash and the Byrds' Roger McGuinn.

He also landed the 1981 hit "Stop Draggin' My Heart Around" with Stevie Nicks and recorded in the 1980s supergroup the Traveling Wilburys with George Harrison, Roy Orbison, Jeff Lynne and Bob Dylan.

"It's shocking, crushing news," Dylan told Rolling Stone in a statement. "I thought the world of Tom. He was a great performer, full of the light, a friend, and I'll never forget him."

Petty cited the Minnesota native as his No. 1 inspiration and backed Dylan on a full tour in 1986 that included the first-ever concert at the Metrodome in Minneapolis.

"He gave us a kind of courage that we never had," Petty later said of the Dylan tour. "You really learnt the value of spontaneity."

He and the Heartbreakers came to Minnesota every few years on tour after that, arguably peaking with a two-night stand at Xcel Energy Center in 2006 when Pearl Jam signed on as the opening act to salute their heroes' 30th anniversary.

In an interview with the Star Tribune before their Xcel Center show this summer, Heartbreakers guitarist Mike Campbell called Petty's partnership with his band "a benign democracy," wherein Petty listened for input but always had the last say.

"Fortunately, most of the time he's right," said the guitarist, who then spoke extra-warmly of the frontman. "He's my best friend. He's an amazing artist. He's a good guy. He's a hard worker. He's got a great work ethic. He's determined. He has a healthy ambition to be the best."

Reviews were consistently favorable from their summer tour, which wound down with a three-night stand at the Hollywood Bowl only a week ago. Sonia Grover, talent buyer at First Avenue in Minneapolis, caught one of those shows as her first-ever Petty concert.

"So many hits, and he seemed to be in good spirits for sure," said Grover, who was stunned by the news.

In typical Petty fashion, he resisted cashing in and declared this summer's tour his final go-round with the Heartbreakers. But he did tell Rolling Stone before the outing, "I'd be lying if I didn't say I was thinking this might be the last big one."

Petty was honored in Los Angeles this past February when, on the eve of the Grammy Awards, he was named MusicCares Person of the Year. The Foo Fighters, Nicks, Lynne, Randy Newman, Jackson Browne, Norah Jones and George Strait were among those who sang his songs at the charity concert, though Petty made a point of paying his respect to the younger bands in attendance, including Cage the Elephant and the Head and the Heart.

"They're gonna carry this forward, and we have to be there to support them," he said at the podium in his unmistakable, nasally drawl, "because there ain't nothing like a good rock 'n' roll band, people."

Star Tribune writer Jon Bream and the Associated Press contributed to this report.

Chris Riemenschneider • 612-673-4658

Twitter: @ChrisRstrib