Toxicology tests for Liam Payne found multiple substances in the singer's system at the time of his death, according to a report from ABC News.

A preliminary autopsy of the former member of One Direction detected cocaine, crack cocaine and benzodiazepine, a widely prescribed class of sedatives and anti-anxiety medications sold under the brand names Valium, Xanax and Klonopin, among others.

Payne, who was 31 when he fell to his death at a hotel in Buenos Aires, Argentina,, last Wednesday, also had a recreational drug known as "pink cocaine" in his system.

The drug cocktail, which also goes by the name Tusi, typically comprises a mix of methamphetamine, ketamine, MDMA, and more, according to the U.S. Drug Enforcement Agency. In a report last month, the agency warned that the blend of substances was being sold across multiple locations in Manhattan, New York.

Payne's body will remain in Argentina pending a complete autopsy report, according to sources who spoke to ABC News.

Prior to Payne's death, staff at the Buenos Aires hotel contacted local authorities about a guest who was acting erratically and appeared to be "drunk with drugs and alcohol."

During their call, the employees told emergency services they feared the guest "could do something that threatens [his] life" because he was staying in a third-story room with a balcony.

When first responders arrived less than 10 minutes later, they found Payne's body in the hotel courtyard and pronounced him dead at the scene.

A preliminary postmortem last week determined Payne died "from multiple traumas and internal and external bleeding."Over the weekend, hundreds of fans gathered to mourn the singer at impromptu vigils in London and Paris.