YouTuber Jack Maynard - who left I'm A Celebrity... Get Me Out Of Here! when offensive tweets he posted in 2012 emerged - has apologised for saying some "pretty disgusting things".
The tweets, which prompted allegations of racism and homophobia, were published in the Sun newspaper while Maynard, 23, was in Australia.
He said he was "young" and "careless" when he posted them.
In an online video, Maynard added: "I've been really stupid in the past."
The show told viewers Maynard - who has more than 1.2m subscribers to his YouTube channel and is the younger brother of singer Conor Maynard - had left the jungle on Tuesday.
A spokesman said he had departed "due to circumstances outside camp".
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In a video posted on his YouTube channel, Maynard confirmed he was back in London.
"The least you deserved was for me to come home and sit down and talk to you and explain everything that has been going on," he told his subscribers.
"I'm so sorry to anyone that I offended, anyone that I upset, anyone I made feel uncomfortable."
He said he had "messed up" adding: "I've tweeted some bad things, some horrible things, some pretty disgusting things that I'm just ashamed of."
"I was young I was careless, I just wasn't thinking, this was back when I had just left school and I didn't know what I was doing."
Jack MaynardImage copyrightITV
The social media star, who revealed it was his 23rd birthday, added: "All I can do is beg and encourage that you guys don't make the same mistake as well.
"Don't put anything online you wouldn't say to your mum."
Maynard appeared on Tuesday night's show, but presenters Ant and Dec confirmed his removal half-way through the programme.
His representative later said the star realised the language used in the now-deleted tweets was "completely unacceptable".
They said Maynard agreed with the decision to leave the show, which was "made by his representatives and ITV".
He had been one of 10 contestants taking part in the programme, which started on Sunday.
