US based Wells Fargo became the latest bank to face cyber-attack, launched by a group pledging retaliation for an online ‘anti-Muslim’ video that sparked violence in Muslim countries.

A group calling itself "Cyber fighters of Izz ad-din Al qassam" has claimed the responsibility for the online attacks.

The group revealed that Wells Fargo and other banks would be targeted for the second week under the name "Operation Ababil," meaning "Swarm."

About 220 customers of Wells Fargo have lodged complaint with sitedown.com, a website that tracks website outages saying that they face problem as they tried to log onto Wells Fargo websites.

Last week, the group launched attacks against the websites of Bank of America, New York Stock Exchange, Citigroup, JP Morgan Chase while US Bank and PNC Bank were also hit in the latest attack.

Iran has rejected reports by the US officials claiming its involvement in hacking into several US banks over the past year as part of their broad cyber operation.

The US White House is planning to issue an executive order intended at securing US computer networks from cyberattacks.

In February this year, operators of US stock exchanges, Nasdaq and BATS have confirmed that their respective public websites became victims of a denial of service (DOS) attack.

Iran has barred access to Google and Gmail in a bid to enhance cyber security and oppose a movie against Islam that has triggered protests across the Muslim world.

YouTube has been blocked in Pakistan and Bangladesh after the site refused to remove the trailer of an ‘anti Islamic’ movie.