Neymar has been asked to appear before Rio de Janeiro state prosecutors "urgently" to give a statement regarding reports he is holding a five-day New Year's party for 150 guests.
However, the player's media officer denies the Brazil and Paris St Germain superstar is hosting any event.
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Authorities said they had received several complaints about the event, which Brazilian media reported was being held at the player's luxury condominium in Mangaratiba, around 105km down the coast from Rio.
State prosecutors said in a statement Neymar and the condominium's representatives had been asked to provide "details about the number of people invited, the party's organisation and the health measures adopted".
However, Neymar's media officer Day Crespo told Reuters the player "will not host any party this year, we are in the middle of a pandemic and he is with his friends and family".
Crespo said the player had flown to the southern resort of Balneario Camboriu in Santa Catarina state.
VIDEO: Rio residents react to football star Neymar's New Year party rumours.
Brazil media reports say Neymar is organising a huge party at his luxury beachside mansion despite the pandemic. His lawyers deny the reports but Neymar, usually active on social media, remains silent pic.twitter.com/oWg8unUjSX
— AFP News Agency (@AFP) December 30, 2020
The 28-year-old posted a picture of himself on Instagram earlier on Wednesday which he tagged as being from Balneario Camboriu.
The player himself has not commented on the reported party since the news broke in Rio de Janeiro newspaper O Globo on Saturday.
English outlet The Sun has reported various models, including the likes of Kiki Passo, Michelle Nevius and Jessica Bartlett, had flown in from overseas after being invited by Neymar over Instagram.
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After details of the event were revealed in the paper, the agency organising it said it would be subject to strict health rules to try to prevent the spread of the COVID-19 virus.
The event was private and all relevant permissions have been obtained, it added, without mentioning Neymar or the name of any host.
Earlier in the day, newspapers said guests had started arriving at the luxury condominium where the player owns property.
Reports said he had bought a disused hangar for the event and required all guests to give up their cell phones to prevent photos and videos leaking online.
The pandemic has killed more than 192,000 people in Brazil, a higher death toll than in any other country bar the United States.
On Wednesday alone, 1,194 people were reported to have died from COVID-19, the Health Ministry said.
The city of Rio de Janeiro, where millions of people gather each year on Copacabana beach to watch the world famous firework display every New Year's Eve, has cancelled this year's event.
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