The body of Liam Payne cannot be released until further toxicology reports have been completed, an Argentina prosecutor said.
The One Direction star's father Geoff Payne is currently in Buenos Aires to arrange the repatriation of his son's body following the 31-year-old's tragic death on 16 October.
A representative of the Public Prosecutor's Office informed Mr Payne that the results of the toxicology and histopathological report, complementary to the post-mortem, would be necessary to decide on the release of his son's body.
The final toxicology results are not expected to be made public for some weeks, but the initial report suggested evidence of exposure to cocaine, an official told the Associated Press, but stressed the initial results do not offer an accurate reading of how much was circulating in his blood when he died.
For the investigation, expert reports are being carried out on mobile phones, computers and security cameras, which the Prosecutor's Office said, "require a longer analysis time".
Meanwhile, the National Criminal and Correctional Prosecutor's Office also said that reconstruction of the events, which has involved taking numerous statements from hotel workers and medical professionals, is "still ongoing".
Liam fell from the third-floor balcony of the Casa Sur Hotel, with a post-mortem report saying he died of multiple traumas and "internal and external haemorrhage".
Among those paying tribute to the star following his death were his fellow bandmates Niall Horan, Louis Tomlinson, Zayn Malik and Harry Styles, as well as his former partner Cheryl, who is the mother of Liam's seven-year-old son, Bear.
In a statement, the singer's family said they were "heartbroken" adding: "Liam will forever live in our hearts and we'll remember him for his kind, funny and brave soul."
Liam's older sisters Nicola and Ruth also shared heartbreaking tributes, with Nicola calling her brother an "angel who just lived for making people smile and happy" while Ruth said Liam's ability to make her laugh is what she "loved most" about him, adding she was "in awe" of his talent.
The Wolverhampton-born musician found fame on The X Factor when music mogul Simon Cowell put Liam with Niall, Louis, Zayn and Harry to form One Direction - one of the best-selling boy bands of all time.