A police reconstruction of how the woman was stuffed in a suitcase after being abducted.
The mysterious online criminal syndicate behind the kidnapping of a British model has boasted of its "huge generosity" in letting her go "because she is a mother".
It emerged this morning how the woman was drugged, handcuffed and loaded into a car boot in Milan before being driven 200km to a farmhouse in Turin where she was kept for six days.
But the organisation, known as Black Death, then performed the u-turn and took her back to Milan, warning in a letter she would be "eliminated" if she went to the police or spoke negatively about them.
The woman, 20, whose identity has not been revealed, was held prisoner for a week after being drugged with ketamine, authorities said.
At a sensational police press conference in Milan her captor was named as Polish-born Lukasz Herba, 30, who is accused of trying to sell her on the internet for €300,000 ($480,000) through Bitcoin.
When officers arrested him he was found in possession of a pamphlet on Black Death which offers the sexual services of women for auction on the dark web.
A picture supposedly uploaded to the organisation's website showed a topless woman tied up alongside details including measurements and nationality in an apparent advertisement - although the image is believed to have been taken from an unrelated pornographic film.
Police say the British model was lured to an abandoned shop near Milan's Central Station with the promise of a photoshoot, only to be drugged, handcuffed and put in a suitcase.
Corriere della Sera reported the model had been lured to the fake shoot from Paris and was then loaded into the back of a car and driven to an abandoned shop south of Milan, before she was then taken on to a farmhouse near Turin 120 miles away.
It is thought she was kept in the bag for two-and-a-half hours and stayed in Turin for six days. Reports in Italy say Herba told officers he had sex with the model but it is unclear whether it was consensual and police are still investigating the claim.
Italian police say the offender demanded €50,000 to free her and "threatened to kill her" if she told officers what happened to her.
Authorities said the kidnappers were going to release her "because she had a 2-year-old child" and their "rules exclude kidnapping mothers".
In a letter sent to the victim upon her release, Black Death told her that a "mistake" had been made in capturing her.
It added that she had been let go after one of its men made "a clear and solid stance in your case".
Officers seized Herba, who is believed to live in the West Midlands, near the British Consulate on July 17 as he was accompanying the model there and said he confessed to the crime.
Police said she was held for a week in abandoned offices in the city and officers are now looking for accomplices after the model told them she was "attacked by two people".
Prosecutors in Italy said Herba was linked to the Black Death criminal organisation that works on the dark web.
They also alleged Herba had dealings in "chemicals and poisons" as he faced a pre-trial hearing before magistrate Anna Magelli in Milan on Friday.
Reports in Italy said the woman has given statements to police and prosecutors aided by lawyers from the British Consulate.
A Milan court heard the woman arrived in Milan on July 11 and was seized near the central station when she was drugged with ketamine.
Prosecutors described the kidnapping as a "very well-organised seizure" and added he was contacted over the internet two days later with requests to "buy" her for sexual purposes.
Police say they are still unclear whether the kidnappers were running an online scam to con "buyers" out of money or whether they actually intended to sell her on.
Officers went through Herba's phone and computer and said they found photos of the woman and material stating she was for sale, while hair from both the model and Herba was found in the boot of his car.
It is understood the police investigation involved reconstructing the kidnapping scene and studying CCTV footage from the area.