The US Federal Reserve has admitted that one of its internal websites was briefly hacked, according to Reuters.
Reuters reported the Reserve had confirmed a breach had occurred but said no critical functions or key data were compromised.
"The Federal Reserve system is aware that information was obtained by exploiting a temporary vulnerability in a website vendor product," a Federal Reserve spokeswoman said.
"Exposure was fixed shortly after discovery and is no longer an issue. This incident did not affect critical operations of the Federal Reserve system."
At the time of publishing the Reserve had not responded to V3's request for comment on the attack.
Meanwhile, Anonymous has also claimed the attackers successfully stole the personal information of more than 4,000 US bank executives.
The collective issued a statement via Twitter alleging to have leaked the information.
The post included purportedly included an employee's login information, credentials, IP addresses and contact information.
Although the Federal Reserve has not commented on the authenticity of the information posted, Sophos senior technology consultant Graham Cluley told V3 it could well be legitimate.
"It sounds like there was a weakness in a piece of third-party software being used on a Federal Reserve web server," Cluley told V3.
"Whether it had been kept up to date with patches or not is unclear. It certainly sounds plausible. Lots of organisations have poorly patched or poorly configured software on their web servers which could potentially help hackers scoop up sensitive information."
Anonymous' statement credited the attack as being a part of its ongoing OpLastResort campaign.
Anonymous' OplastResort campaign started earlier in January and in protest against the treatment of internet activist and Reddit founder Aaron Swartz, who died last month.
Swartz was facing trial on charges that he had stolen over four million articles from the JSTOR online archive and journal distribution service.
Prior to the attack on the Federal Reserve hackers operating under the Anonymous banner also claimed responsibility for an attack on the US Department of Justice website.