The DNA demand applies to all Congolese children adopted in Belgium from November 2013 and comes as an 18 month investigation builds up a head of steam.
Prosecutors want the tests to find out the extent of the trafficking in Congolese children to Belgium, which infamously colonised a region including the present day Democratic Republic of Congo.
Investigators have identified at least four cases where a Congolese child adopted in Belgium had living biological parents thousands of miles away. The parents, who lived in the countryside, were convinced to send their children to a holiday camp in the capital Kinshasa.
The children were instead put in the Tumaini orphanage, which investigators found was hastily closed recently, before being flown to Belgium.
Julienne Mpemba, 41, is suspected of being behind the orphanage trafficking and facilitating the kidnaps. She claimed that she gave around 50 Congolese children “a new future in Belgium” and that she did not receive money in the process.
At the moment, all of the adopted Congolese children remain in Belgium with their adopted families. Their adoptions can be cancelled, but it is possible that a family judge could rule that a child stays with the adoptive parents.