Published on March 2, 2015

How long until the world launches an all out massive attack on ISIS?

Authorities fear that ISIS will launch an “on-camera slaughter of major proportions” after kidnapping at least 300 Christians in Syria last week, a top US official told The Post.

“What is very disconcerting is that they rounded up all of these people, and we know from experience that they usually kill their captives on film and in the most brutal fashion,” the official explained.

“Remember, they’ve already gone from beheading one person on camera to, most recently, beheading 21 people on camera,” the official added, referring to the nearly two dozen Coptic Christians slaughtered on video released last month.

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“This could very well turn into an on camera slaughter of major proportions.”

The terrorists have garnered the ire of Pope Francis, who has called the 21 killed Christians “martyrs’’ — and led a massive pray-in at St. Peter’s Square in Rome on Sunday for others held captive.

Read more: NY Post