Gary Richrath Gary Richrath

Gary Richrath, the guitarist and songwriter for REO Speedwagon, has died at the age of 65. A publicist for the band, Erik Stein, confirmed Richrath died on Sunday to The Huffington Post, but did not specify a cause of death.

Richrath joined REO Speedwagon in 1970 and stayed with the rock group until 1989. He helped write many of the band's biggest hits, including "Take It on the Run," "Ridin' the Storm Out" and "In Your Letter."

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Richrath reunited with REO Speedwagon for special one-night performance in 2013 to benefit tornado victims in Central Illinois, where the band is from.

"Gary was both a unique guitarist and songwriter, and the embodiment of the tough guy with a heart of gold," band member Kevin Cronin said in a statement on the group's website. "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."