In messages on its Twitter account, hacker group TeaMp0isoN also hinted it will soon leak details of cases against President Barack Obama.
"[Eight] Court Cases against @SarahPalinUSA that have been whitewashed," it said.
The supposed data about the cases against Palin were uploaded to Pastie.org.
A later tweet said "the next bunch of cases that will be leaked will be related to Obama."
The TeaMp0isoN group had been in a rivalry of sorts with Lulz Security, which had also hacked into many government and corporate websites.
Last June, the group vowed to reveal the identities of Lulz Security members, who TeaMp0isoN said were "nothing but a bunch of script kiddies."
A week after some of their members were arrested, hacktivist groups Anonymous and Lulz Security remained defiant, telling the Federal Bureau of Investigation and international law authorities to "expect us."
In a message posted on Pastebin.com, the two groups said they were amazed and amused by an FBI official's claim that "chaos on the Internet is unacceptable."
"We become bandits on the Internet because you have forced our hand. The Anonymous bitchslap rings through your ears like hacktivism movements of the '90s. We're back - and we're not going anywhere. Expect us," they said.
"We are not scared any more. Your threats to arrest us are meaningless to us as you cannot arrest an idea. Any attempt to do so will make your citizens more angry until they will roar in one gigantic choir. It is our mission to help these people and there is nothing - absolutely nothing - you can possibly to do make us stop," they added.
The post appeared to be a reply to statements by FBI deputy assistant director Steve Chabinsky where he was quoted as saying that even if hackers may have social causes, "it's entirely unacceptable to break into websites and commit unlawful acts."
Last Tuesday night (Manila time), 21 hacking suspects were arrested in the United States, United Kingdom and the Netherlands.
Of the 21, 16 were arrested in the US and one in the UK, while Dutch police arrested at least four more.
But Anonymous and LulzSec said they found acceptable the following acts:
- Governments lying to their citizens and inducing fear and terror to keep them in control by dismantling their freedom piece by piece.
- Corporations aiding and conspiring with said governments while taking advantage at the same time by collecting billions of funds for federal contracts we all know they can't fulfill.
- Lobby conglomerates who only follow their agenda to push the profits higher, while at the same time being deeply involved in governments around the world with the only goal to infiltrate and corrupt them enough so the status quo will never change.
As to Chabinsky's claim that the Internet has become so important they have to make sure it "does not become the Wild Wild West," they said:
"Let me ask you, good sir, when was the Internet not the Wild Wild West? Do you really believe you were in control of it at any point? You were not."
"That does not mean that everyone behaves like an outlaw. You see, most people do not behave like bandits if they have no reason to," they added.