An unknown hacking group referring to itself as the "Shadow Brokers" has reportedly hacked the National Security Agency and is trying to auction off the data it grabbed.

The group posted some of the data for free on a Tumblr blog over the weekend, Foreign Policy reported Monday, though it had been inexplicably removed by Monday evening. The rest of the information was available for buyers to place bids on using the cryptocurrency bitcoin.

In addition to possible intelligence data, analysts said the data included code linked to private security developers including Cisco, Fortinet, TopSec Technology, and Juniper Systems. The NSA has a well-known history of hacking into high profile tech companies in order to insert so-called "backdoors" for breaching security products before they hit the market, which could explain how they ended up stolen in a breach of the agency's servers.

The Shadow Brokers claimed the information came from hacking the Equation Group, a highly sophisticated threat actor linked to the NSA for its connection to projects like the Stuxnet virus, the malicious software that for years ravaged Iranian nuclear centrifuges.

In an English-challenged message, the group talked up its purported success at breaching the agency. "We find many many Equation Group cyber weapons. You see pictures. We give you some Equation Group files free, you see. This is good proof no? ... You break many things. You find many intrusions. You write many words. But not all, we are auction the best files."

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"Elites is making laws protect self and friends [and] lie," the group added. "Then Elites runs for president. Why run for president when already control country like dictatorship? We want make sure Wealthy Elite recognizes the danger cyber weapons, this message, our auction, poses to their wealth and control. Let us spell out for Elites. Your wealth and control depends on electronic data."

Guccifer 2.0, the individual allegedly responsible for recent high profile attacks on organizations that include Democratic National Committee and the campaign arm for House Democrats, brushed off the group's claims, using an expletive to refer to it as "nonsense" and adding, "The hacking world operates differently."

But if the group did manage to hack the NSA, the feat raises a number of questions, including the extent of the breach and the number of additional actors that could have stolen information from the American intelligence community.