It was a rare meeting at the Vatican, Pope Francis convening with his Middle East envoys to discuss the plight of Christians threatened by Islamic State in Syria and Iraq.

Vatican ambassadors to both countries were in attendance, to express their concerns about the extremist group's fight to form a "caliphate" in the region..

Islamic State has killed a number of Christians and others who won't convert to Islam.

The pope's issued strong criticism of the militants in the past -- saying no group should use violence in the name of God.