Members of the hacker group Anonymous defaced the website on Friday of the law firm that defended a US Marine who faced charges in connection with the 2005 killing of 24 Iraqi civilians.
Anonymous, in a statement which appeared on the website of the law firm of Puckett and Faraj, also claimed to have published online three gigabytes of private email messages of attorneys Neal Puckett and Haytham Faraj.
"The contents of these email messages include detailed records, transcripts, testimony, trial evidence, and legal defense donation records pertaining to not only Frank Wuterich but also many other marines they have represented," Anonymous said.
Puckett served as the lead defense lawyer for Staff Sergeant Frank Wuterich, who faced a US military court martial last month in connection with the killings in the Iraqi town of Haditha.
Wuterich, 31, admitted one count of negligent dereliction of duty but manslaughter charges were dropped as part of a plea deal.
Wuterich, who led an eight-man squad whose other members have all been let off, was sentenced to 90 days of confinement and reduced in rank to private but will serve no jail time under the deal with prosecutors.
Anonymous, in the statement on the puckettfaraj.com website, said it wanted to bring attention to the "brutality of US imperialism."
"Can you believe this (expletive deleted) had his charges reduced to involuntary manslaughter and got away with only a pay cut?" it said.
"Meanwhile Bradley Manning who was brave enough to risk his life and freedom to expose the truth about government corruption is threatened with life imprisonment," the group said in a reference to the US soldier accused of leaking classified US documents to WikiLeaks.
A receptionist who answered the phone at Puckett and Faraj said the firm's website was now offline. She said there would be no immediate statement about the hacking incident.
Following the Wuterich verdict, Ali Mussawi, spokesman for Iraqi Prime Minister Nuri al-Maliki, said "the punishment is not suitable with the crime that was committed."
"We will keep pursuing the legal channels to fight for the rights of our citizens who were victims of indiscriminate shooting, without having committed any sins," Mussawi said.
The hacking of the Puckett and Faraj website was announced shortly after Anonymous released a recording on YouTube of a conference call between FBI and Scotland Yard agents discussing operations against the hacker group.
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