Eddie Van Halen is among the rock stars who have come out to honour the life of AC/DC co-founder Malcolm Young.
The Australian guitarist passed away at the age of 64 on Saturday (18Nov17) after suffering from dementia, and Van Halen rocker Eddie will deeply miss his friend, who he toured with in the 1980s.
"It is a sad day in rock and roll," the 62-year-old wrote on his Twitter account. "Malcolm Young was my friend and the heart and soul of AC/DC. I had some of the best times of my life with him on our 1984 European tour.
"He will be missed and my deepest condolences to his family, bandmates and friends."
Mandy Moore's ex Ryan Adams has also paid tribute to the late AC/DC legend, noting Young is behind some of the most classic songs in rock history.
"He was the founding member of AC/DC & the engine that roared behind the most powerful band in the world," Adams tweeted. "He wrote Back In Black, Highway to Hell, You Shook Me All Night Long, Highway to Hell (sic), so many songs...Travel safely to the stars, Malcolm. Legend."
Drummer Mike Portnoy, Whitesnake singer David Coverdale and members of the Zac Brown Band have also paid their respects to Malcolm.
AC/DC bandmembers have already released a statement mourning Malcolm's death on their website.
Young, who created AC/DC with his brother Angus Young in Sydney in 1973, left the band in 2014, when his family confirmed he was suffering from dementia. The group have continued to perform without him, although they have now lost three more members.
Malcolm is survived by his wife Linda and two children.
The family have asked for donations to be sent to The Salvation Army, instead of flowers.