Trans-Siberian Orchestra Founder Paul O'Neill Dies at 61 (UPDATE)

Paul O'Neill -- founder of the Trans-Siberian Orchestra -- has died after a private battle with a chronic illness, the band confirms. He was 61.

Law enforcement tells TMZ ... Paul was found dead in a Tampa hotel room. There are no signs of foul play, but police don't know yet how long he was deceased before they responded to a 911 call. We're told the Medical Examiner has his body now.

Paul's band says, "The entire Trans-Siberian Orchestra family, past and present, is heartbroken to share the devastating news that Paul O’Neill has passed away from chronic illness," a statement said on the band's official Facebook page.

"He was our friend and our leader -- a truly creative spirit and an altruistic soul. This is a profound and indescribable loss for us all."

O'Neill created the band back in 1996 and hit it big with its metal-infused take on classic Christmas songs. The band has sold more than 12 MILLION albums.