The Middle East Media Research Institute (MEMRI) has published a summary of the history and religious motivation of Sunni-Shi'ite cyber attacks:
"The Sunni-Shi'ite cyberwar started in 2007 when a group of Sunni hackers calling itself "XP Group" threatened to attack all Shi'ite websites on the Internet, and proceeded to hack some 120 Shi'ite sites."
Sunni groups escalated the cyber confrontation in 2008 adding the religious motivation behind the attacks:
"Among them were two groups called Shabab Al-Salafiyin and Al-Ayyoubiyoun. The latter declared on various forums that the war against Shi'ite sites was a form of jihad that brought one closer to Allah."
The article concludes with quotes from Egyptian columnist Diana Muqallid:
"Battles between Sunni and Shi'ite sites are being waged [on the Internet], with each side virtually killing and harming the other by targeting the websites of religious figures, political leaders, and media outlets... In our lifetimes, [we have seen] journalists murdered, incarcerated, tortured and exiled. Media outlets have been closed in our region or placed under supervision, [and their premises] have been burned down. Electronic attacks convey the very same sentiment of wanting to negate the other..."
Recent Rise in Sunni–Shi'ite Tension (Part I): Sunni – Shi'ite Hacker War on the Internet