NATO ambassadors are gathering for an emergency session to gauge the threat the Islamic State extremist group poses to Turkey, and the actions Turkish authorities are taking in response.

The extraordinary meeting Tuesday at NATO headquarters is only the fifth such emergency meeting in the 66-year-history of the alliance. Turkey requested the session under Article 4 of the treaty, which empowers its 28 member states to seek such consultations when they consider their "territorial integrity, political independence or security" to be in jeopardy.

Turkey's request followed an IS suicide bombing near Turkey's border with Syria that left 32 people dead and an IS attack on Turkish forces, which killed a soldier.