Twisted Sister guitarist Jay Jay French told the Los Angeles Timesthat his Adrenaline Mob bandmates called an ambulance after they were unable to wake him up on the band's tour bus. He was declared dead shortly after 11a.m. after arriving at a hospital in Poughkeepsie, N.Y.

The Time reported that he died of an apparent heart attack and had these words from French, "His drive was the heart and soul of the band's sound, the engine that drove us. We lost a friend and a legend."

Twisted Sister frontman Dee Snider had the following tribute, "Today I lost a brother. Anthony Jude Pero passed away. A.J. was the final piece in a band that would become an international sensation and one of the greatest live rock acts to ever hit the stage. His sledgehammer assault on the drums helped drive Twisted Sister and me to greatness and inspired me to rock every single show. My heart breaks knowing I will never feel the power of his beat behind me, or turn to see his face smiling broadly from the sheer joy he got from doing what he loved. I will always remember that smile. RIP my friend."

The band posted the following on their Facebook page, �The members of Twisted Sister are profoundly saddened to announce the untimely passing of our brother, AJ Pero. The band, crew and most importantly the family of AJ Pero thank you for your thoughts and prayers at this time.�

Adrenaline Mob wrote, "We write this with tears in our eyes & our hearts broken to pieces.. our beloved brother AJ Pero peacefully passed away in his sleep this morning on the bus. We are in complete shock & our hearts & prayers go out to his family. It has been nothing short of an honor to have shared the stage with such a beautiful soul & legend! We love you AJ, rest in peace." They also posted a photo of the band sitting around a camp fire with the caption, "We will cherish this last picture we all took together on tour forever! What a great night we had... we'll miss you buddy!" See the photo here

AJ's friends in Avenged Sevenfold wrote this tribute, "We want to send our thoughts out to the family of A.J. Pero of Twisted Sister and Adrenaline Mob. He passed away last night while on tour.