A Love Island spokesperson told MailOnline in a statement: 'Niall has left the villa for personal reasons and won't be returning to the show'.
But Mirror Online now claim it was due to "health reasons", with Niall and Love Island bosses deciding it was time for him to leave.
A representative for the ITV2 show confirmed that he had departed the programme yesterday afternoon for undisclosed "personal reasons".
In Tuesday's episode Alex announces: "For personal reasons unfortunately he [Niall] can't continue or come back to the villa". He's such a great guy.More news: Dem lawmakers seek criminal corruption probe of EPA's Pruitt
This latest showdown could well have repercussions for Adam, with a recoupling coming up that will put the girls in charge of who they wind up partnered with, and we all know what happens to Islanders who don't get picked...
'He was actually my friend, my buddy'.
'And I look forward to catching up with him and having some fun with him outside'.
Niall had become one of the series favourites with his cheeky personality and references to Harry Potter.
All Love Island couples could be forced to recouple on Tuesday night - hours after Niall Aslam's shocking exit was revealed.More news: Trump wants to stop provocative 'war games' with South Korea
Fans on Twitter, including MP Stella Creasy, seemed upset by the news.
Niall was one of this year's original islanders; he coupled up with Kendall Rae-Knight at the first coupling before Adam Collard arrived and stole her away.
It's not yet clear how Niall's departure will affect Georgia's status in the villa.
Both the islanders and viewers have been kept in the dark over the reason for his exit.More news: Toyota makes record $1 billion investment in ride-hailing firm Grab
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