Ivana Smit had threesome with Alex Johnson and Luna Almaz before death

The mystery of Dutch model Ivana Smit's plunge to death from the 20th-floor apartment of business tycoon Alex Johnson and his wife, Luna Almaz, still continues. The latest addition to the story being the married couple finally opening up about the mishap, claiming they had a threesome with the 18-year-old, moments before her death.

Johnson, the American crypto-currency tycoon, and his Indonesian wife, Almaz, had invited the teen model to a "swinger's party" where drugs and alcohol were involved, as The Sun reported. The couple has revealed how post the accident they have been receiving death threats, after private investigators revealed that the girl had been murdered.

Their personal accounts revealed that they had had sex with Ivana weeks before the December 7, 2017, tragedy, and also again, shortly before she mysteriously fell 14 floors down to her death. Her naked body was found on the sixth floor of the Persiaran Capsquare, where they were supposedly partying.

Addressing the whole issue and everything they have been going through, Johnson, 40, said: "This case is an object lesson in how false claims and fake news can come close to destroying people. We never intended to make the details of our marriage public. Now we fear our own lives are in danger, and we have no choice."

His wife Luna shared: "When I talk about her death, my hands are shaking; I have a pain in my heart. I feel so sad. It's awful. But because I have been fighting to prove my innocence, I haven't been able to grieve."

Despite police having stated that there were 'no criminal elements' involved, British investigators hired by her parents claim it was a murder. On Sunday, the Dutch lawyer hired by them also shared that autopsy reports prove there was 'male DNA' in her dead body, meaning she had sex hours before her death.

"In the Netherlands, you can be prosecuted if you commit sexual acts on someone who is unconscious or under reduced consciousness," Sebas Diekstra, the family's hired lawyer, told De Telegraaf.

The Smit family spokesman Fred Agenjo also shared with De Telegraaf that it is illegal in the Netherlands to have sex with someone if they are heavily intoxicated to the point of incompetence.

"There were huge amounts of drugs found in Ivana's body. She was no longer competent," Agenjo said. "If anyone still had sex with an 18-year-old girl who was in that condition, that's not good. They should stay away from someone under such circumstances."

As per the couple's reports, the night they partied together with Ivana, all three had been drinking heavily and they were aware that Ivana had been taking drugs too. A recent CCTV footage that has surfaced the internet also shows Ivana being carried into the lift, just hours before the teen fell to her death.

It was also revealed that Ivana had been introduced to the couple weeks before at a nightclub by a mutual friend. Almaz shared that the model had herself come up to her and asked her to dance with racy moves, even though they didn't have sex then.

The roots of the successful model's mysterious death haven't' entirely been accessed as of yet, but her family hired Williams-Thomas — a former Surrey cop and the award-winning presenter of The Other Side of Jimmy Savile documentary on ITV — to dig out exactly what had happened.

Speaking to Belgium's TV Limburg earlier this year, Williams-Thomas shared: "From the evidence that I have collected this week, and other information that we have through the forensics, we are in a position to say very clearly: If this was being dealt with in the UK, it would be treated as a homicide investigation."