The US Federal Reserve confirmed that hackers breached one of its internal websites over the weekend, however, it had no effect on critical functions of the US central bank.

According to Reuters, a spokesperson said the Federal Reserve system is aware theinformation was obtained by exploiting a temporary vulnerability in a website vendor product.

"Exposure was fixed shortly after discovery and is no longer an issue," said the spokesperson.

"This incident did not affect critical operations of the Federal Reserve system."

Recently, the hacker group, Anonymous, had posted details of 4,000 US bank executives on the website of the Alabama Criminal Justice Information Center. The site has been offline since the incident.

"Some registrants also included optional information consisting of home phone and personal email. Despite claims to the contrary, passwords were not compromised," the US Federal Reserve said in a statement.

The attack has been executed as part of the hackers’ new ‘Operation Last Resort’ campaign over the prosecution of hacktivist Aaron,Swartz in January 2012.

In 2012, Anonymous targeted major US banks which included Bank of America, JPMorgan Chase, Citigroup, Wells Fargo and Capital One.