Black Sabbath and Dio singer Ronnie James Dio has died after losing his battle with stomach cancer.
Tributes from the metal world immediately poured in. Metallica's Lars Ulrich wrote a heartfelt letter to Ronnie James Dio on the band's official site, thanking the singer for his contribution to music: "Ronnie, your voice impacted and empowered me, your music inspired and influenced me, and your kindness touched and moved me."
Rage Against The Machine guitarist Tom Morello was similarly effusive in his praise for the veteran rock vocalist. "RIP Ronnie James Dio," wrote Morello on Twitter. "One of rock's greatest singers. Cranking 'Mob Rules' in his memory. Thanks Ronnie for rocking me like crazy."
His wife and manager Wendy Dio posted a statement on his official site which read: "Today my heart is broken, Ronnie passed away at 7:45am 16th May... his music will live on forever."
In addition to performing with with Elf, Rainbow, Heaven & Hell and Black Sabbath (whom he joined after replacing Ozzy Osbourne in 1979), as well as his own band Dio, Ronnie James Dio is also famous for popularising - some say inventing - the "devil's horns" hand gesture.
We interviewed Dio in June 2009 - head here to read his reminiscences on Ozzy Osbourne, 'Holy Diver', and starring in South Park.
Ronnie James Dio pictured backstage with members of Metallica. The singer was famously diminutive in stature - 5'4" - a fact which he accepted with good humour. "It's not the size of the pencil," he once said. "It's how big you write your name."
Dio was born Ronaldo Giovanni Padovan in 1942, the only child of Italian parents. He began calling himself Dio in 1961, inspired by mafia member Johnny Dio.
His Black Sabbath bandmate Tony Iommi issued the following statement: "The man with the magic voice is a star amongst stars, a true professional. I'll miss you so much my dear friend."
Meanwhile, here's Smashing Pumpkins frontman Billy Corgan on Ronnie James Dio: "I only got to meet him once and I can honestly say he was the nicest person I have ever met in music. Ronnie was a true gentleman, and obviously one of the best rock singers there will ever be. What a sad loss today."