Authorities in Argentina are continuing to investigate the circumstances surrounding the death of former One Direction star Liam Payne.

The singer fell from a balcony in Buenos Aires on 16 October.

The Public Prosecutor's Office has told his father that toxicological and other tests need to be completed before his body can be released and returned to the UK.

Information from emergency services and other authorities has been released, and has started to build a picture of the events.

Payne was staying in a hotel in the upmarket neighbourhood of Palermo in the Argentine capital.

He had been at the hotel for two or three days, according to staff, and had been in the country to visit his former bandmate Niall Horan.

Horan was in Argentina on tour and the pair had remained friendly since One Direction's 2016 split.

Payne posted on Snapchat earlier this month that he was visiting Horan for a catch-up, saying: "It's been a while since me and Niall have spoken, we've got a lot to talk about."

He added: "No bad vibes or anything like that, but we need to talk."

Payne attended the show, again posting social media videos of himself and girlfriend Kate Cassidy singing and dancing at the concert.

The BBC also spoke to fan Noelia Verón - who saw him on 30 September and then again at the concert on 2 October.

She said "He was fine. Later people said he was either drunk or on drugs. But that wasn't the case at all. He talked to us, hugged us and even made jokes."

When Veron saw him at Niall's show, she said he was "dancing, waving and cheering" and "seemed to be enjoying himself".

We also know the pop star had visited a friend's house in Argentina in the days before he died, again with Cassidy.

But when Payne fell to his death on 16 October, Cassidy had already left the country.

Payne had been documenting much of his trip on Snapchat, including pictures of food, plans to play polo, and jokes about his hair.

But none of his posts featured the CasaSur hotel, where he had been staying shortly before his death.

We know a call was made to emergency services around 17:00 local time (21:00 BST) by hotel staff, with requests to respond to a hotel guest "who is overwhelmed by drugs and alcohol" and "destroying his room".

"I don't know if the guest's life is in danger. But he has a room with a balcony and we're a little afraid that he might do something life-threatening," said the hotel's front desk manager in a second call.

Payne's room was on the third floor and had a balcony about 14m (45ft) above an interior courtyard.

It is thought he fell from the balcony at about 17:07 local time.

Police arrived minutes later. Hotel staff told them a loud sound had been heard in the courtyard, where Payne's body was discovered.

He was pronounced dead at the scene, with the emergency services saying there had been "no possibility of resuscitation".

Payne's body was removed from the hotel at about 20:30 local time and an autopsy was carried out that evening.

It established that he had suffered "multiple traumas" and "internal and external haemorrhaging" according to the public prosecutor's office.

A preliminary report stated he had 25 injuries, which were "consistent with a fall from a great height".

It also added that he may have been fully or partially unconscious when he fell.

Some media outlets have reported preliminary results of toxicology tests, which the Associated Press (AP) news agency said suggested evidence of exposure to cocaine, quoting an unnamed official.

But they said the official stressed that the initial results don’t give an accurate idea of how much was in his blood when he died.

Authorities also interviewed five witnesses to help piece together Payne's final hours, including three hotel workers as well as two women who had been with the singer but had left the hotel before his death.

Investigators also want to establish the "possible involvement of third parties in the events prior to the victim's death".

Hotel staff on the emergency call highlighted that Payne was "destroying his room", and police say they found the room in "total disorder".

A bottle of whiskey, a lighter, a passport and a mobile phone were found.

The room was said to have "various broken items" and medication was found, including anxiety drug clonazepam and other over-the-counter medications.

Evidence and fingerprints were also collected to be analysed in a lab.

Local media also published pictures purportedly from his room, showing a TV with a broken screen, multiple bottles, cans, candles, aluminium foil and a half-full glass of champagne.

The prosecutor's office said substances that appeared to be "narcotics and alcoholic beverages" were found in the room with pieces of furniture and other objects broken.

Payne's death is being treated as suspicious by prosecutors, which means more needs to be established about what happened before his death and who he was in contact with.

"Numerous statements were also taken to reconstruct the victim's final hours and the scene of the events, a process that is still ongoing with hotel workers, acquaintances, technical and medical professionals, and other people linked to the victim through their work," the National Criminal and Correctional Prosecutor's Office said on 22 October.

Expert reports are being carried out on phones, computers, photos and videos from security cameras, which the prosecutor's office said require more time.

The full toxicology report must also be completed.

Payne's father Geoff visited the Argentine capital after the singer's death and has "stated to the prosecutor his willingness to testify about everything he knows about his son's life that could help the investigation", the office said.

Full coverage of the death of Liam Payne: