Chechen leader Ramzan Kadyrov announced the evacuation from Iraq of eight children and four women, originating from Russia and Kazakhstan, who had been left behind in areas liberated from ISIL's fighters.
Mr Kadyrov, head of the mainly Muslim region of Chechnya, wrote on Instagram: "This evening, a plane will arrive in Grozny from Iraq with the latest group of our citizens."
He specified that the plane would bring "12 people — four women and eight children aged from six months to nine years old".
The women were all mothers of children on the plane.
Mr Kadyrov has said the Russian government wants to return Russian women, not just children, from Iraq.
Some women went out to Iraq and Syria following their husbands who had become fighters and taking their children with them.
Interfax news agency later reported from Grozny airport that Russia's children's ombudswoman Anna Kuznetsova and senior Chechen officials had met the plane carrying the 12 evacuees.
It was the largest group to be flown to Chechnya from Iraq, and the first flight to include adults. Seven children were flown back on a similar flight last month.
Mr Kadyrov is leading a drive to return the children of parents who left Russia and other ex-Soviet countries in the region to travel to Syria and Iraq to join the jihadist group.
Iraqi police and army commanders have said that many of the foreign ISIL fighters who mounted a final stand in Mosul came from Russia, particularly Chechnya, and other former Soviet bloc countries.
Mr Kadyrov has vowed to bring back all the Chechen children in Iraq, saying that "the parents of almost all of them are dead".
The Chechen strongman said those on the latest flight included a woman from Chechnya with three children and two women with sons from the Russian cities of Tver and Tyumen and a citizen of ex-Soviet Kazakhstan with three children.
Children's ombudswoman Kuznetsova told RIA Novosti that she planned to fly on to Moscow with the rescued children.
She held talks with Mr Kadyrov in Grozny on Thursday, footage on Grozny TV showed.
The ombudswoman wrote on Facebook that while in Chechnya she met a boy who was flown back from Mosul last month after his father took him aged two to Syria in 2015 without his Chechen mother's consent.
RT state-controlled television reported in August that the Russian authorities were trying to return 48 minors from Mosul, whose parents had taken them from Russia to Syria and Iraq. It said the evacuation of the children was delayed because they lacked Russian documents.
The total of such children could be much higher as Ms Kuznetsova has gathered a list of more than 350 children who were reportedly taken from Russia to Syria and Iraq.
After two separatist conflicts with Moscow, the largely Muslim region of Chechnya is now under the tight control of Mr Kadyrov's feared security forces.