Local police said Payne had fallen from the third floor of a hotel in the capital Buenos Aires on Wednesday evening.
He is said to have suffered “extremely serious injuries”.
Alberto Crescenti, head of the state emergency medical system, said on Argentinian television that Payne fell into a courtyard of the CasaSur Hotel in the trendy Palermo neighbourhood.
He declined to answer further questions about the incident, including whether Payne jumped from the balcony or fell by accident.
Pablo Policicchio, a spokesperson for the security ministry of Buenos Aires municipality, said police were called to the hotel in response to an “aggressive man who could be under the influence of drugs or alcohol”.
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Fans gather outside the hotel where Liam Payne died
Payne’s social media post hours before death
Payne had posted on Snapchat in the last few hours, and in one video he said it was a “lovely day here in Argentina”.
“Just enjoying coffee and breakfast, even though it’s like 1pm,” he said. “Literally sleep in every day until like 12. We’re such losers.”
The star spoke about “going to ride some horses” and said: “Think I’m going to play polo again which is going to put me out of action for about six weeks.”
“It’s going to be a nice day,” he added.
It was not clear when the videos were filmed, but were posted hours before his death.
Why was Payne in Argentina?
Payne was in Buenos Aires to attend the concert of his former One Direction bandmate Niall Horan.
He was seen dancing at his show two weeks ago at the Movistar Arena alongside his girlfriend Kate Cassidy.
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