Anonymous has attacked a company linked to the New York Police Department in what the group said was a show of strength and that it will not relent following the arrest of several LulzSec members.
The New York Iron Works site was defaced on Friday by the group with messages in support of jailed members of LulzSec.
Shortly after the defacement, the Anonymous IRC Twitter feed said that the attacks were launched as retaliation for the recent arrest of members of the LulzSec hacking group.
LulzSec is believed to have been an offshoot of Anonymous and the two groups had been working together on the Antisec hacktivist campaign.
"Do you really think that pulling a Hector to arrest a Jeremy is a won battle? Think again," AnonymousIRC told authorities.
The Tweet referenced the online aliases of LulzSec members Hector Monsegur and Jeremy Hammond, two targets of the raid.
Authorities arrested Hammond and four other members following evidence gathered by Monsegur, who had been working for several months as a police informant.
Shortly after the attack, the group took down the site of Australia's Department of Justice for what the group claimed was a failure to properly support the country's citizens.
The attack was given a vote of support by Wikileaks, which recently partnered with Anonymous to publish hacked information from military supplier Stratfor.
"We do not condemn such protest actions provided they do no harm," the group tweeted.
"They are an expression of public sentiment."
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