Riot posted the following message on the band’s website and Facebook page Wednesday:

“To friends and fans of Mark Reale and Riot, we are deeply saddened to confirm that Mark has lost his battle with a lifelong illness. Your thoughts and prayers are appreciated by Mark’s family, friends, and bandmates at this difficult time.”

The band’s Facebook profile picture, as well as the front page of Riot’s website, has been changed to a picture of Reale along with the words: “Rest in peace … Mark Reale June 7,1955 – January 25, 2012.”

Reale formed the heavy metal band in 1975 along with drummer Peter Bitelli, bassist Phil Feit and vocalist Guy Speranza. The group, which replaced Feit with Jimmy Iommi and added guitarist Louie Kouvaris, released its debut studio album, Rock City, in 1977. Riot’s fifteenth and most recent studio album, Immortal Soul, was released in October 2011.

The current lineup features vocalist Tony Moore, drummer Bobby Jarzombek, bassist Don Van Stavern and guitarist Mike Flyntz.

Earlier this month Pollstar.com reported that Reale was in critical condition in a San Antonio, Texas, hospital because of complications from Crohn’s disease. The guitarist has suffered from the inflammatory bowel disease, which often causes severe abdominal pains, for most of his life. Before passing away, Reale had reportedly been in a coma since suffering a subarachnoid hemorrhage Jan. 11.

Click here for Riot’s website and here for the band’s Facebook page.