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Col. Bruce Hampton died hours after taking part in a celebrity-filled birthday celebration Monday night at Atlanta’s Fox Theatre.

The singer-guitarist turned 70 years old last week, and the event was honored with a four-hour show.

During the encore, Hampton collapsed while onstage and was taken to the hospital.

Shortly before 3 a.m., former Allman Brothers Band guitarist Derek Trucks confirmed on Facebook that Hampton had died.

Celebration Turns Tragic

When Hampton slowly fell to his knees during the finale of the concert, fans and musicians alike thought it was another one of his quirky performance acts.

As 14-year-old guitar phenom Brandon “Taz” Niederauer tore into a blistering solo, the 70-year-old man lay motionless just feet away, his arm draped over a speaker.

For several more minutes, dozens of musicians — including John Popper of Blues Traveler, Warren Haynes of The Allman Brothers Band and John Bell of Widespread Panic — jammed away to one of Hampton’s favorite songs “Turn On Your Love Light” and laughed as they waited for him to get up.

But Col. Bruce never did.

While wealth and fame eluded Hampton, he was widely acknowledged as an influence on other leading musicians. He also played the role of a songwriting band manager in Billy Bob Thornton’s 1996 film “Sling Blade.”

Thornton joined Hampton on stage for the “Love Light” encore and beamed as Hampton belted out the first part of the tune with his bluesy growl. Hampton paced across the stage and teased the audience by pretending to leave before he re-emerged. Then he fell to his knees.

When people began to realize this was no stunt, the band abruptly ended the song and a hush fell over the crowd. Stunned fans looked at one another and asked, “What just happened?”

“We’re going to take care of business backstage here,” Thornton said. “Thank you so much. We love you so much. Thanks for honoring Bruce Hampton on his 70th.”

Outside the venue, fans gathered on the street as an ambulance and firetruck arrived. Hampton was carried out of the theater on a stretcher. People cheered when he was loaded into the ambulance and shouted “Brrruuuccccee” as they had done throughout the night.

Hampton showed no sign anything was amiss before his collapse. He appeared on stage early in the four-hour night, conducting and singing with a band. Later, he played and sang several tunes, including “I’m So Glad” as well as “Fixin’ to Die,” a song he had performed many times before. This time, though, the lyrics turned out to be prophetic:

Feeling funny in my mind, Lord

I believe I’m fixing to die

Well, I don’t mind dying

But I hate to leave my children crying

Longtime Atlanta musicians such as Michelle Malone took to social media Tuesday, pouring out their admiration for the man they say encouraged and inspired them. “I will miss your wry sense of humor, your big weird brain, your great big kind heart, and your genius and endearing approach to music,” Malone wrote. “Thank you for refusing to accept almost any boundary in music.”

‘Granddaddy Of The Jam Scene’

The Tennessee native started his long musical journey in the 1960s when he founded Atlanta’s Hampton Grease Band, which toured with The Grateful Dead. Hampton eventually was dubbed “the granddaddy of the jam scene” and was known as a “surrealist” musician. His surrealist world was called Zambiland.

“It’s our absurd religion. It’s basically built on nonsense,” he said. “It’s creative processing. One and one is two, but what’s one?”

In a recent interview with WABE’s Lois Reitzes, Hampton recalled a special moment in his 53-year musical career.

“We were playing a Georgia Tech fraternity, and there was a band with Johnny Jenkins and Jaimoe of the Allman Brothers and Otis Redding on bass, and I went ‘Oh, that’s how it’s done.’”

Five years ago, Georgia Gov. Nathan Deal honored the musician with the Governor’s Award in the Arts and Humanities.

NPR reporter Andrew Flanagan contributed to the report.