A British model was kidnapped and held captive for several days in Italy by a man who threatened to auction her off on the dark web, police have said.

The 20-year-old woman, who has not been identified, is believed to have been drugged with ketamine and put into a suitcase by Polish-national Lukasz Herba on 11 July.

Herba, who is reported to currently live in the West Midlands, is accused of luring the woman to Milan from Paris with a promise of a fake photoshoot. After the 20-year-old arrived, she was drugged, stuffed in a bag and loaded into the back of a car and driven to a farmhouse near Turin around 120 miles.

Herba is said to have kept the woman at the house for six days before dropping her off at the British consulate in Milan.

Police are investigating if the woman was abducted so she could be sold off as a sex slave in a Bitcoin auction on the dark web.

Italian media reports that Herba has links to the "Black Death" criminal organisation that works on the dark web.

While it is unclear why the kidnapping came to an end, it is the reported the 20-year-old was released because she had a two-year-old child and the gang's 'rules' prevent them from kidnapping and trafficking mothers.

Italian newspaper Corriere della Sera reports the woman was told she could be freed if a ransom of €50,000 (£45,000, $58,000) was paid, although it is not known if this money was paid.

Police are now working to identify Herba's accomplices and established what happened to the woman while she was help captive. The 20-year-old has given statements to police.

Lukasz Herba
Lukasz Herba by Italian police was arrested while returning the woman to Milan Police handout