Not very long ago, large parts of northern Iraq were under the control of ISIS. That is no longer the case. But this week, Iraqi security forces say they arrested several suspected members of the group. Authorities are also wary in the north of Iraq, in the semi-autonomous Kurdish region. The Kurds have been frontline fighters against ISIS, but some of them have also joined ISIS. As Rebecca Collard reports, the Kurdish regional government in Iraq is taking measures to make sure that it never happens again.