Richrath played with the band from 1970 until 1989 and wrote their U.S. Bilboard top five hit Take It On The Run. He performed on 12 REO Speedwagon albums, including their self-titled debut and their biggest selling record Hi Infidelity before leaving the band to embark on a solo career which yielded one album.

In a post on Sunday, REO Speedwagon singer Kevin Cronin writes, "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."

No cause of death had been released as WENN went to press.