Six Belgian orphans born to families belonging to ISIS have arrived in Belgium, Foreign Minister Didier Reynders said on Friday.
"The six children from Syria have just arrived in our country," Mr Reynders said on Twitter.
"The children are now being monitored and supervised by the competent local state attorneys and youth support services," he added.
One of the country’s prosecutors said the children were “psychologically supervised” during the journey, and that their ongoing mental and physical well-being were a priority.
"It should be noted that these children have spent a long period of time in Syria under difficult conditions," the prosecutors’ statement added.
The children arrived in Belgium just a day after being handed over to officials by Kurdish authorities in northeast Syria.
The statement said that one of the orphans no longer was a minor.
Officials have previously said that four of the six orphans expected to return were older than 10, but that none was a suspect.
Belgium had announced the transfer of the children from Kurdish-controlled camps in Syria after the deaths of their jihadist parents.
Belgium is one of several European countries wrestling with the dilemma of what to do about citizens trapped in Syria following the defeat of the IS.
Some are reticent to accept captured extremist fighters, but the cases of children and non-combatant wives have proved more complicated for Western authorities.
The bulk of IS fighters and family members who were captured when its so-called caliphate collapsed are being held in Syria in Kurdish-run camps.
According to Belgian media reports, 50 to 60 Belgian children under 18 are in the camps of Al Hol, Roj, and Ain Issa in Syria.
Belgium was one of the European countries which, relative to its size, saw one of the larger contingents of extremists set off for the Syrian battlefield.
Authorities estimate that 400 adults have headed to jihadist-controlled areas since 2012 and 150 were still considered "active and in place" at the end of last year.
Syria's Kurds have detained hundreds of foreigners suspected of fighting for ISIS, as well as thousands of related women and children, during the US-backed battle against ISIS in Syria.
The Kurdish-led Syrian Democratic Forces expelled the extremist group from its last patch of territory in the eastern Syrian village of Baghouz in March, after larger than expected numbers of families emerged from the ruins.