Tom Petty dies at the age of 66. A Rock-n-Roll Legend.

After news broke Monday that legendary singer Tom Petty had been hospitalized, the music world reacted almost immediately.

Though it was erroneously reported earlier in the afternoon that Petty had died, his longtime manager confirmed in a statement obtained by ABC News that Petty died at 8:40 p.m. PT Monday evening.

Petty was 66 years old.

Most social media posts, which began pouring in from celebrities this afternoon, have been of sadness and appreciation for the man who helped create many hits during his 40 years in music.

"I loved Tom Petty and I covered his songs because I wanted [to] know what it felt like to fly," wrote John Mayer.

Added actor Kiefer Sutherland: "Today America lost one of its musical giants. Thank you Tom Petty for all the music. To me you will live forever."

With classic songs like "Free Fallin'," "American Girl" and "I Won't Back Down," Petty entered the Rock and Roll Hall of Fame in 2002.