BERLIN (AP) — German authorities say a 30-year-old woman who allegedly was a member of the Islamic State group has returned to Germany with her three children.

German news agency dpa reported Sunday the woman and children, whose identities were not revealed, arrived Saturday night in Frankfurt from Irbil in Iraq.

It is believed they were in a detention camp in northern Syria.

Authorities said the woman would be investigated among other things for her membership in the IS group, but that there was no arrest warrant for her.

Earlier this month, Turkey stepped up the return of suspected foreign IS members back to their countries of origin.

Germany has said it will check the background of all suspected Islamic State group members deported back to Germany to assess the risks they pose.