Rylan tweeted: "Absolutely disgusted someone would do that".
The reality star posted a video on Twitter confirming she was still alive, and admitted she had "been through hell", due to the false announcement.
Paying tribute, former Big Brother's Bit On The Side host hailed Shelton as a 'lovely lady'.
A source close to the star's family, who still refer to her as Rodrigo, told MailOnline that her relatives thought she had actually died and were "grieving this morning", but also revealed that some suspect it was a publicity stunt. People think "She looks good now, she can go out, have sex now with guys or get married or things", but people don't know the journey I've been through.
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Shelton previously made headlines when she came out as trans, having transitioned to female in 2012.
"You can't see what I've been through; you can't see my heart or feelings".
Rebekah, formerly Rodrigo, on series 10 of Big Brother. Rebekah was a lovely person.
"God, how terrible! I'm so sorry". "It was a big step to go full time as a woman".
However, Rebekah has posted a video to her Twitter account to explain that she is alive and well, and that a hacker gained access to her account and posted the tweet.
An official statement on Rebekah's Twitter account confirmed she had passed away "unexpectedly on Wednesday night". "We ask that you respect the family's privacy at this time".
One emotional fan commented: "This is so sad".
Giving her advice to others who may be in a similar situation, she said: "I would say to them, don't look at me and think, oh she looks unbelievable, I want to be like her".
She appeared on the show as a man, but after she left she went through transition and said that it was sparked when she met a man she was in love with. One of the most loveable BB housemates.
A string of media outlets picked up the story after the official Big Brother account posted a tribute to the star - but in a freakish twist, she was later confirmed to be alive.
She revealed that she's on holiday and added in her caption for the video: 'I'm not dead!