Irbil, Iraq (CNN) -- A day after Britain's military launched its first airstrikes against ISIS in Iraq, the question is: Who will be next to join the U.S.-led coalition in its air campaign against the extremists who have seized a swath of Iraq and Syria? As Turkish soldiers and tanks took up position along the border with Syria on Tuesday, Turkey's government put a motion before its Parliament asking for authorization to take military action against ISIS -- the terror group that refers to itself as the Islamic State. Lawmakers are expected to debate the measure in a special session Thursday before voting, according to Anadolu, Turkey's semiofficial news agency.
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Bomb blasts kill 39 people, including 30 schoolchildren, U.N. chief says
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U.N. chief condemns attack as an "act of utmost depravity''
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Coalition is at an important moment, John R. Allen, retired general, says
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Turkey deploys troops along its border with Syria as lawmakers consider intervention
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That number will only rise as costly munitions are used -- and could soar further if more @placeholder forces are committed to the operation.
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Turkey's debate over whether to step into the fray comes as the flood of refugees from Syria has escalated, with 150,000 people fleeing to @placeholder in recent days.