US National Security officials accused the Iranian government of carrying out cyber attacks against the websites of US banks JPMorgan Chase and Bank of America, NBC News reported Thursday.

A Middle East group of hackers claimed credit for the denial-of-service attacks, that made both websites unavailable to some customers earlier this week, citing the anti-Islam video that mocks the Muslim Prophet Muhammad as the reason behind the attacks.

Denial-of-service (DDos) attacks seek to disrupt websites and other computer systems at the targeted organization by overwhelming their networks with computer traffic.

US security sources rejected the hackers' claims of responsibility, telling NBC News that this is "a cover" for operations of the Iranian government, and suggesting the attacks are in response to US sanctions on Iranian banks.

The Financial Services Information Sharing and Analysis Center (FS-ISAC), a financial services industry group, issued a warning to US banks, brokerages and insurers on Wednesday to be on heightened alert for cyber attacks after Bank of America and JPMorgan Chase experienced unexplained outages on their public websites.

Reuters contributed to this report.

Click here for full Jpost coverage of the Iranian threat

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