A wave of bank cyber attacks has resumed, with many JPMorgan Chase & Co. customers unable to access their Internet banking accounts.

Chase’s online systems, under attack all day Tuesday, were still not completely operational by evening. “We’re working to get things back to full speed,” bank spokesman Michael Fusco said.


No customer data had been compromised, and the bank’s mobile, telephone and ATM networks were functioning properly, he said.

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Chase was targeted by the latest in a series of denial-of-service attacks, which overwhelm websites with phony requests so that legitimate customers can’t get through.

A group identifying itself as Izz ad-Din al-Qassam Cyber Fighters has been attacking American banks off and on since September. The group, based in the Middle East, says the attacks are retaliation for a video, produced by amateur U.S. filmmakers, that mocks the prophet Muhammad.


In a pastebin.com post, the group threatened to attack U.S. banks on Tuesdays, Wednesdays and Thursdays “because of widespread and organized offends to Islamic spirituals and holy issues.” It said the attacks would stop if the video disappeared from the Internet.

The website sitedown.co, which allows Internet users to report crashes of corporate sites, recorded 213 reports of problems with Chase’s website in the 24 hours that ended at 7:40 p.m. Pacific time Tuesday.


The site showed 917 reports of Chase outages over the last month, compared with 453 at AT&T;, 415 at Netflix, 351 at Bank of America and 107 at Wells Fargo.

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