George Tickner, the co-founder/rhythm guitarist for Journey, has died at age 76.

Tickner’s death was confirmed via Journey leader/guitarist Neal Schon, but he did not disclose a cause of death.

“Journey Junkies, I have some very sad news. George Tickner, Journey’s original rhythm guitarist and songwriting contributor on their first three albums, has passed away. He was 76 years old,” Schon, 69, wrote on Facebook. “Godspeed, George…thank you for the music. We will be paying tribute to you on this page indefinitely.”

“Our condolences to his family and friends, and to all past and present band members. So heartbreaking. I think we need to do a group hug,” Schon continued.

Tickner played on Journey’s debut studio album and has songwriting credits on the band’s second and third studio albums.

He left Journey shortly after the release of their debut album to attend Stanford Medical School on a full scholarship.