U.S. intelligence operatives covertly sabotaged a prominent al-Qaida online magazine last month in an apparent attempt to sow confusion among the group's followers, according to officials.

The operation succeeded, at least temporarily, in thwarting publication of the latest issue of Inspire, the English-language magazine distributed by al-Qaida in the Arabian Peninsula. When it appeared online, the text on the second page was garbled and the following 20 pages were blank. The sabotaged version was quickly removed from the online forum that hosted it, according to independent analysts who track jihadi websites.

It's unclear how the hacking occurred, although U.S. intelligence agencies have invested heavily in cybercapabilities in recent years. Security officials said the recent operation was only the latest U.S. attempt to disrupt al-Qaida's online propaganda.