Rock and Roll Hall of Fame member Tom Petty, 66, died on Monday, Oct. 2 at 8:40 p.m. PT. at UCLA Santa Monica Hospital after being found unresponsive on Sunday, Oct. 1.

Petty rose to fame in the 1970s as the frontman for Tom Petty and the Heartbreakers, selling more than 80 million albums over his 40-plus-year career and recording such hits as “I Won’t Back Down,” “Runnin’ Down a Dream,” “Free Fallin’” and more.

Petty’s music transcended the rock genre, as evidenced by the outpouring of messages posted on social media by many country artists, including Shania Twain, Reba McEntire, Midland, Jason Isbell, the Oak Ridge Boys and more.

Is this true????????? Please say it's not!!!!

A post shared by Reba (@reba) on Oct 2, 2017 at 1:21pm PDT

Got the news of Tom Petty's condition just before last nights show here in U.K. Just found out his passing was confirmed. He was such a true musical hero and his songs will live forever. This one seems even more poignant in these last couple days and decided we'd open the show with it. RIP @tompettyofficial and Have fun jamming with your Rock n Roll heroes in Rock n Roll Heaven. ??????

A post shared by Randy Houser (@randyhouser) on Oct 2, 2017 at 10:34pm PDT

Thanks for giving me the soundtrack of my youth. Rest in peace Tom Petty. ?This has been a rough one. Love to al… https://t.co/VApwkJP6od pic.twitter.com/b3usHKCdcz

— Midland (@MidlandOfficial) October 3, 2017

Music lost another legend today #RIPTomPetty pic.twitter.com/zSaibzqoUW

— Rodney Atkins (@RodneyAtkins) October 3, 2017

Tom Petty has indeed passed on… very sad … pic.twitter.com/s895c9BgJu

— The Oak Ridge Boys (@oakridgeboys) October 3, 2017

RiP Tom Petty. So terrible. @Col_JonHensley would be devastated.

— Shooter Jennings (@ShooterJennings) October 2, 2017

Now, Tom Petty. Today sucks. RIP to my favorite rocker ever. Regret I never saw him live. Prayers go out to his family…

— Justin Moore (@JustinColeMoore) October 2, 2017

I believe @tompetty is in Heaven entertaining the beautiful souls that were lost last night in #Vegas. That’s what I believe right now. ?

— Maggie Rose (@IAmMaggieRose) October 2, 2017

More bad news on an already sad day #RIPTomPetty

— The Oak Ridge Boys (@oakridgeboys) October 2, 2017

No……not Tom Petty.

— Martina McBride (@martinamcbride) October 2, 2017

I can’t think of an important moment in my life without an accompanying Tom Petty song. Every night we walk off stage to his music. So sad.

— Jason IsBOO (@JasonIsbell) October 2, 2017

Just when I thought today could not get any worse…
R.I.P. Tom Petty. Thank you for your beautiful music and inspiration.

— Kid Rock (@KidRock) October 2, 2017

So sad to hear of the passing of Tom Petty. Such an incredible, inspiring artist. I’ll treasure fond memories of our time spent together this past summer ❤ pic.twitter.com/HvSgARxzm3

— Shania Twain (@ShaniaTwain) October 2, 2017

Fly safe, Tom. Thankyou for your magic. Tell the angels we need a hand down here. ?

— Clare Bowen (@clarembee) October 2, 2017

Been doing #tompetty You Wreck Me on the @cmorganmusic #americanstoriestour with @jasonhoard… https://t.co/lAZjg9XztN

— mac powell (@macpowell) October 3, 2017