From Iraq to New York, a busy week for Islamic State group

Little known to the wider world 18 months ago, the Islamic State extremist group has muscled its way into the international spotlight by carving out a self-declared caliphate in the heart of the Mideast, beheading its opponents and foreign journalists, and attracting radicalized youth as far afield as Paris, London and New York.

The militants' once seemingly unstoppable push across Syria and Iraq has slowed to a crawl in recent months as the United States, its Arab allies and even rival Iran work to roll back the group and ultimately defeat it. Despite those efforts, the extremists show little sign of crumbling under the weight of international efforts to crush it.

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