Watch Price of Fame: The Liam Payne Story as new details emerge about the singer's death

New details have emerged in the investigation into Liam Payne's death.

Among the new details, multiple sources with direct knowledge of the investigation told ABC News that police reviewed CCTV footage that appeared to show several drug exchanges between a dealer and a hotel employee before Payne's death. Sources said police are investigating whether the hotel employee supplied Payne with drugs.

Payne was also seen twice in CCTV footage sleeping in the hotel lobby with a bottle of whiskey in his hand, the sources told ABC News.

Watch Price of Fame: The Liam Payne Story – A Special Edition of 20/20 airing Sunday, November 3rd at 10pm ET on ABC and streaming on Hulu beginning November 4th.

Sources say police never believed Payne's death was suicide or intentional.

Previously, sources told ABC News that a partial autopsy also found he had several substances in his system that day, including “pink cocaine” – a recreational drug that is typically a mixture of several drugs, including methamphetamine, ketamine , MDMA and others as well as cocaine, benzodiazepines and crack. According to the sources, an improvised aluminum pipe for taking drugs was also found in his hotel room.

Police also noted the presence of two female escorts at the hotel in the hours before Payne's death, according to multiple sources with direct knowledge of the investigation.

Payne offered $5,000 to two female escorts who were allegedly called through an app in the lobby of the hotel where Payne was staying during his death. He did not pay the escorts, sources said.

Sources also reported that a Rolex was also missing from Payne's hotel room.

ABC News has reached out to the hotel for comment.

Sources added that Payne's body is expected to be returned to his family next week.

According to the British Embassy in Buenos Aires, Payne's father Geoff has been in Buenos Aires since October 18, trying to have his son's body returned to England for burial. The release of Payne's body depends on the court's findings in the criminal case.

According to Argentine State Police, Payne died on October 16 after falling from his third-floor hotel room in Palermo, Buenos Aires. He was 31.

Emergency services were called to deal with a man who was acting erratically and may have been under the influence of alcohol, Alberto Crescenti, the director of SAME, Buenos Aires' emergency medical service, previously told ABC News. Crescenti said Payne's body was found in the hotel's courtyard, where he was pronounced dead at the scene.

A preliminary autopsy report from the Argentine prosecutor's office revealed on October 17 that Payne died of “multiple traumas” and “internal and external bleeding.”

Twenty-five injuries were reported on Payne's body. The report stated that Payne's head injuries were sufficient to cause death and that the cause of death was related to the height of his fall.

Argentine officials searched the hotel on October 23 as part of the ongoing investigation into the late singer's death.

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