HSBC has become the latest bank to see its Web site knocked out by a group protesting the release of a film mocking the prophet Mohammed.
The bank has confirmed that its servers came under a denial of service attack yesterday, which affected several of its Web sites, including the US, UK and First direct portals.
No customer data was affected but customers were prevented from using online services, including Internet banking before the issue was resolved at 03:00 UK time.
Over the last two days, BB&T and Capital One have also been hit, the latest in a long line of financial institutions that includes Bank of America, JP Morgan Chase and Wells Fargo, to have been targeted in recent weeks.
On Tuesday a group called QassamCyberFighters posted its latest statement on Pastebin, confirming: "With a little searching, we still found the anti-Islamic offensive film on the Internet. Thus the chain of cyber attacks on U.S. banks will continue this week."
The statement also had a message for US defence secretary Leon Panetta, who on Monday warned that the country "has the capacity to locate" the attackers and "hold them accountable for actions that harm America or its interests".
Says QassamCyberFighters: "Instead of concerning and spending several billions that won't be good for you, tell your henchmen on YouTube to run remove command on their computers otherwise try to solve the following equation while your banks are howling under pressure from the attacks."