Sharing a sweet baby-faced throwback photo of the pair from their Pop Idol days on Instagram, Gareth wrote: "I can't quite believe the news of my dear friend Darius passing. I'm heartbroken. Darius took me under his wing during our time in Pop Idol, like a big brother; always looking out for me and for that I thank you my friend."
WATCH: Stars gone too soon
He went on to describe Darius, who placed third in the ITV reality show, as "one of the most beautiful, intelligent and gentle souls I was lucky enough to know, a soul that lit up every room," before ending his tribute: "Good bye my friend. Forever in my heart x."
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Popstars alum Jessica Pietersen and Myleene Klass were also among those who shared some touching words about the late singer and West End star.
Gareth shared a throwback photo alongside some sweet words
Myleene, who appeared on the show with her band Hear'Say, honoured him with a never-before-seen snap from the show, which she captioned: "Back at the very start. RIP Darius x" while Liberty X's Jessica Pietersen wrote: "He was an absolute gentleman & I know all of us who did Popstars with him will remember him with huge fondness."
Myleene shared a never-before-seen snap from Popstars
TV and radio presenter Nicki Chapman, who worked as a judge on both Popstars and Pop Idol with Simon Cowell, wrote on Twitter: "There will only ever be one Darius Campbell Danesh. A true gent with a kind soul & mischievous tinkle in his eye."
Darius passed away on Thursday 11 August, although the news was only confirmed by his family in a statement on Tuesday 16 August. It read: "It is with great sadness that we announce the passing of Darius Campbell Danesh. Darius was found unresponsive in bed in his apartment room in Rochester, Minnesota, on August 11 and was pronounced dead in the afternoon by the local medical examiner's office."
It added that the local police department have confirmed that there were no signs of intent or suspicious circumstances and the cause of his sudden death is unknown at this stage. "We ask that you kindly respect our wishes for privacy at this time whilst we come to terms with the tragic loss of our son and brother," the statement concluded.
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