REO Speedwagon guitarist Gary Richrath passed away on Sunday, September 13, as reported by NME. REO lead singer Kevin Cronin shared the news of Richrath, aged 65, through social media, and Erik Stein, the band’s representative, confirmed but did not specify the cause or location of Richrath’s death.

In 1970, Richrath joined the American rock band as the lead guitarist, replacing Steve Scorfina, and recorded twelve albums. Additionally, Richrath penned some of REO Speedwagon’s greatest hits, including “Take It on the Run” and “In Your Letter” and “Ridin’ the Storm Out”.

The band’s singles rose on the charts in the late ’70s before “Hi Infidelity”, the 1981 blockbuster album, sold over 10 million copies and became the biggest selling rock LP of 1981. Richrath recorded his last album with the band, Life As We Know It, before leaving in 1989 to release a solo album titled Only the Strong Survive.

Cronin, who called Richrath his “rock ‘n’ roll big brother” in a 2013 interview, commented in a Facebook post:

My longtime friend and collaborator Gary Richrath passed away earlier today. I feel so sad. Gary was both a unique guitarist and songwriter, and the embodiment of the tough guy with a heart of gold. I learned most of what I know about being in a rock band from Gary Richrath. The entire REO Family mourns his death and shares in the grief of his family, friends, and fans. These words do not come close to expressing the depth of emotions I am feeling at this time.