The 66-year-old singer last performed with the Heartbreakers on Sept. 29.
Tom Petty was reportedly rushed to the hospital on Sunday night after he was found unconscious at his home in Malibu, California.
According to TMZ, the 66-year-old singer went into cardiac arrest and was put on life support at UCLA Santa Monica Hospital.
The website later reported that upon getting to the hospital, Petty did not have any brain activity and a decision was made to pull his life support.
A sergeant for the Los Angeles County Fire Department tells ET that officials responded to a call at 10:45 p.m. on Sunday night at Petty's residence for an unconscious patient who was transported to a local hospital. ET has reached out to Petty's reps.
The music legend -- who is originally from Florida -- recently performed with the Heartbreakers on Sept. 29 at the Hollywood Bowl in Los Angeles. "Tom Petty seemed upbeat, energetic and his performance was great," a concertgoer tells ET. "He bantered with the audience and, at times, seemed sentimental while reminiscing about his 40 years with the band."
The concertgoer adds that Petty showed no signs of fatigue during the concert and appeared healthy and happy.
Another concert attendee also tells ET that the musician was upbeat during his performance. “Tom looked so happy and full of life on Monday night," says the concertgoer. "He told a bunch of stories about his life and talked about how important his bandmates were to him. He ended the concert with two encores”
Petty is next set to appear with his band in New York City on Nov. 8 and 9. He has been touring since April 20.
Petty is best known for his songs "I Won't Back Down," "Runnin' Down a Dream" and "American Girl." He is also a three-time GRAMMY winner, garnering 18 nominations, and a Rock and Roll Hall of Famer.
Additional reporting by Marisa Fassino and Sophie Schillaci.