By Christian Fraser
BBC News, Rome
Italian police say they have broken up a gang suspected of kidnapping illegal immigrants and holding them for ransom.
Illegal immigrants are vulnerable and at risk from those offering help
Police say the gang was helping people escape holding centres in the south of Italy and then taking them captive.
Many of those who land on the southern shores of Italy have already paid large sums of money to the traffickers who arrange their passage.
Now some are being locked up in old abandoned buildings until their family pays a ransom of up to $800 (£400).
The victims were immigrants from Eritrea, Sudan and Morocco, who had travelled to join relatives already in Italy.
In one operation, called Slave, the police arrested seven Sudanese nationals in the town of Crotone, in Calabria, home to one of the biggest detention centres.
But while they have broken up one gang, they suspect there are others involved in the same work.
They were alerted to the problem by one immigrant family who complained about the fee they had been forced to pay.
It can often take families several weeks to find the money.
The problem highlights the difficulties the authorities face coping with huge numbers of illegal immigrants in Italy.
Pressure on the detention centres leads to thousands being let out of the back door, usually with notice to leave the country within a week.
In reality, they disappear into black sector employment.
Most leave the centres with nothing - they are vulnerable and at risk from those offering help.