Last summer, three Chinese girls aged around 15 disappeared from a refugee reception centre in Oravais on Finland's west coast. Two of them were later found in England and were returned to Oravais -- but vanished again.
Finland has six refugee reception centres which house under-age asylum-seekers that have arrived in the country without their parents.
Officials stress say that their job is to provide the children with a place to stay and food. Otherwise, the young asylum-seekers are free to come and go as they please.
So far this year, 17 children have left the centres for good without notifying the authorities. Half of them have vanished from the centre in Turku, which has good ferry connections to Sweden.
The authorities suspect that some of those who have vanished have been the victims of human trafficking, but officials have failed to recognise this before it has been too late and the kids have left the centre on their own accord.
A report about a disappearence is always filed with local police. But there is precious little the police can do. The fate of those who leave usually remains a mystery. Most of them are in their early teens.
Officals suspect that organised gangs may be supplying young unaccompanied asylum seekers in Finland with a passport, visa and money to leave the country.
On Sunday, authorities in Stockholm, Sweden charged a middle-aged Chinese couple with human trafficking. The prosecutor says they intended to smuggle four Chinese children under the age of 15 to Italy or France, and had plans to smuggle another 11 children.
Over 100 Chinese children and youth have applied for asylum in Sweden over the past year, but then disappeared.