In an email interview Wednesday, a self-described member of the so-called al-Qassam Cyber Fighters told ABC News the group was made up of computer-savvy volunteers who have taken to cyber space to spread the protest against an anti-Islam film made in California.
"No government or organization is supporting us and we do not wait for any support as well," the member said. "Do you think that the massive protests in the world are done with support? (In) the same manner (that) millions of Muslims in the world protested, hackers are also part of this protest."
In mid-September al-Qassam issued a declaration online in which the group warned it would be attacking major US financial institutions including Bank of America and the New York Stock Exchange in response to a trailer posted online for the film "The Innocence of Muslims." The film, which insults Prophet Mohammad (PBUH), sparked real-world protests in many countries in September.
In the days following al-Qassam's threats, websites for the institutions named in the online posting, as well as other major banks including PNC and Wells Fargo, experienced Distributed Denial of Service (DDoS) attacks, which overloaded the websites and temporarily knocked many offline.
Cyber security expert and ABC News consultant Richard Clarke said the websites were hit with a deluge of malicious traffic "twice as large as any flood we have ever seen." The attacks did not penetrate the banks' internal network, but kept customers from accessing their accounts online for hours.
While al-Qassam made their online declarations in English and Arabic, many US news outlets, including ABC News, alleged that US officials suspected hackers in Iran had been involved. Sen. Joe Lieberman (I-Conn.) told C-SPAN's "Newsmakers" that the cyber attacks were a "powerful example of our vulnerability" and said he believed they were "done by Iran" as a response to the American and European sanctions on the Middle Eastern nation.
Iran strongly rejected the claim.
A Distributed Denial of Service attack is a relatively unsophisticated cyber operation in which a hacker or group of hackers utilize often pre-written code to inundate a target website with traffic until it is overloaded.