The FBI has launched an investigation into the alleged theft of thousands of 9/11 documents, according to Zerohedge.

A hacking organization known as the Dark Overlord obtained some 18,000 documents from insurers involved in the many cases that arose from the Muslim terror attack on the United States, including Hiscox and Lloyd’s of London.

The law firm Blackwell Sanders Peper Martin, now known as Husch Blackwell, apparently also was involved.

The report cites the Financial Times and two people familiar with the situation as sources.

“The Dark Overlord said it would sell the documents for bitcoin, inviting Isis, al-Qaida and nation states to bid for them online,” the report said.

“Pay … up, or we’re going to bury you with this,” the hackers allegedly claimed. “If you continue to fail us, we’ll escalate these releases by releasing the keys, each time a Layer is opened, a new wave of liability will fall upon you.”

The report said the threat continued: “If you’re one of the dozens of solicitor firms who was involved in the litigation, a politician who was involved in the case, a law enforcement agency who was involved in the investigations, a property management firm, an investment bank, a client of a client, a reference of a reference, a global insurer, or whoever else, you’re welcome to contact our e-mail below and make a request to formally have your documents and materials withdrawn from any eventual public release of the materials.

“However, you’ll be paying us.”

Zerohedge said images of some documents started circulating on Wednesday, and they appeared to show communications related to the World Trade Center.

Hiscox insurance said it learned of the hack months ago.

“The law firm’s systems are not connected to Hiscox’s IT infrastructure and Hiscox’s own systems were unaffected by this incident,” a company official reported. “One of the cases the law firm handled for Hiscox and other insurers related to litigation arising from the events of 9/11, and we believe that information relating to this was stolen during that breach.”

Law enforcement officers in the United Kingdom and the United States were being called in to work on the case.

The 9/11 attacks, which killed 3,000 people, cost the insurance industry an estimated $45 billion. The lawsuits largely have been over who should bear the cost, Zerohedge said.

Husch Blackwell said it had not been hacked, although documents with the letterhead of a predecessor firm were made public by a cyber terrorist group, Zerohedge reported.

“A spokesperson for Lloyd’s said it had no evidence of a breach of their systems, and said in a statement ‘Lloyd’s will continue to monitor the situation closely, including working with managing agents targeted by the hacker group,'” the report said.

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