Jihadis Learn To Hide Data In Digital Images
A member of one of the militant Islamist Internt forums explained to other members how to encode data into digital images, as a way to communicate and relay confidential information and messages safely over the Internet. Abu Muadh al Hamdani, explained the technique, known as Steganography which was mentioned a few years back in an al Qaeda online technical magazine called "The Technical Mujahid" and is thought to have been used by al Qaeda and other operatives for years.
(Thread on al-Firdaws forums)
In October 2001, the New York Times published an article about al Qaeda using Steganographic techniques to encode messages into images, and then transported these via e-mail to prepare and execute the 9/11 attacks.