3 February 2015: IS releases a video of captured Jordanian pilot Muath al-Kaseasbeh being burned to death in a cage, sparking outrage in Jordan, which launches new strikes targeting the militants.
6 February 2015: IS claims a Jordanian airstrike kills American hostage Kayla Jean Mueller. US officials later confirm her death, but say it wasn't caused by a Jordanian airstrike.
25-28 February 2015: IS overruns several Christian villages in Syria's eastern Hassakeh province, taking at least 220 Assyrian Christians hostage.