A 30-year-old man has been arrested in the alleged kidnapping of a young British model who thought she was going to Milan for a photo shoot.

Instead she was drugged, hustled away in a suitcase and handcuffed in a house in northern Italy before being released.

Milan police on Saturday released a mugshot of the suspect whom they identified as Lukasz Pawel Herba, a Polish citizen with British residency.

Police official Lorenzo Bucossi told reporters the 20-year-old woman had gone to Milan for what she thought was a photo shoot and was abducted on July 11, ‘to be sold to the best offer on pornography sites’, according to a police statement.

The suspect was arrested on July 18, the day after he allegedly released the woman and dropped her off at the British consulate in Milan, police said.

The woman arrived in Milan on July 10 and was supposed to do the photography session the next day.

A photographer had booked the session through the model’s agent, but as soon as she stepped inside the Milan apartment for the appointment, she was attacked by two men.

‘The kidnappers loaded the suitcase with the girl (inside) into a car trunk’ and drove to a rural home in a hamlet outside Turin.

In the house, the model was kept handcuffed to a wooden dresser in a bedroom until she was released on July 17.

Police suspect the Polish man advertised the sale of the woman online, while at the same time demanding ransom from the woman’s agent of $US300,000 ($378,150).

Authorities said as far as they knew, no ransom was paid.

Investigators are trying to determine if the suspect had accomplices and was mainly after ransom, or was trying to defraud someone who might have been willing to pay money online for the woman.

They did not identify the model’s agent.

Milan daily Corriere della Sera said the kidnapper let his victim go because he discovered she had a child and considered her unsuitable for the sex trade. But the police official Bucossi told reporters it was unclear why the woman was released.