Meanwhile, it is understood that detectives are continuing to probe into why Ms Ayling agreed to go shopping for shoes with her alleged captor without raising an alarm or trying to escape.
Ms Ayling's close friend, Ms Carla Berlucci, told BBC TV that Ms Ayling, whom she has known for five years, is a "good girl, a little bit naive".
The arrest of a suspect in the alleged abduction and Ayling's account of a startling ordeal have garnered global media attention since details about the case emerged over the weekend.
British model Chloe Ayling was kidnapped while on business in Italy in early July. The text said she was "for sale by Russian mafia". But the group told her that she has to strictly follow several sets of instructions for her own protection.
It has been reported she told police she had developed a trusting relationship and even shared a bed with her kidnapper, who gave her chocolate and underwear, but she said he had not sexually assaulted her.
Further investigations are ongoing in order to "identify possible accomplices" and clarify the motive, police said.
Chloe Ayling, a 20-year-old mother of one, said she was attacked by two men after arriving in Milan in mid-July to take part in a photo shoot arranged by her agent.
He said: "It seems incredible".
"I have been through a terrifying experience", Ayling said in a prepared statement after she returned to the United Kingdom on Sunday.
The lawyer, Francesco Pesce, said his client had been threatened with death throughout the ordeal and decided it was better to cooperate with Herba.
"So she abided to his request, "let's go and buy groceries" and "you need shoes, let's go buy shoes" and she didn't try to flee".
She said: "That's what I would like to know, who's behind this".
"I was supposed to see her yesterday, but she's signed with a new celebrity agency and they've told her not to talk to me", Bellucci said. They took her to the British consulate.
Milan police officer Lorenzo Bucossi told reporters the group the suspect allegedly worked for offered "mercenary services" on the dark web.
On July 17, one week after Ayling flew into Milan, a man named Lukasz Pawel Herba reportedly dropped Ayling off at the British consulate in Milan, reportedly after releasing her from bondage. He said the person who made the booking had "a website, previous pictures, details of his studio, details of what the shoot was going to be, times, locations, fee " everything".
Police say Herba had demanded a $300,000 ransom from the model's agent that he said would stop an online auction for the woman.
A polish citizen, 30-year-old Lukasz Herba, was later arrested and charged with kidnapping for the alleged crime. He said he initially believed that the properties would be used to store clothes, but was later brought into the kidnapping scheme when he needed money to pay for his treatment for leukemia.