but that is not what happened. from the original washington post article:
"The Post is withholding most plot details, including the name of the city, at the urging of officials who warned that revealing them would jeopardize important intelligence capabilities." [1]
That means that the Post, and presumably other media outlets, have access to a bunch of details about the intelligence source. It is very possible that through this leak these details could escape the media outlets and get into ISIS allied hands, and that therefore the intelligence source could be terminated.
