As we reported earlier today, legendary Velvet Underground frontman and solo artist Lou Reed has died at the age of 71. The veteran rocker had undergone a liver transplant in May, but no cause of death has been officially announced.

Reed, who collaborated with Metallica a couple of years, ago, is highly respected in the rock world, having influenced a tremendous amount of bands. With a death of this magnitude in the rock world, a slew of musicians and bands have reacted via Twitter, including Nikki Sixx, Dave Navarro, Motorhead, Flea and several others. See their tweets below: