US federal agency confirms data breach in wake of claims by ransomware group

Roman said the affected system was “quickly shut down when ​the breach was discovered,” and that an investigation is ongoing. A separate statement ​posted to the agency’s website said the ATF is coordinating closely with the Department of Justice and that the episode has been designated a “major incident.”Neither Roman nor the statement ​identified a possible culprit for the breach.

Read More:Major tech companies call for defensive surge to defeat AI-driven hacks. The breach raises concerns because ​ATF systems can contain sensitive law enforcement data, including details on ongoing investigations. The "major incident" ‌designation ⁠means the breach could result in harm to national security or civil liberties and triggers congressional reporting requirements.

The ATF is a federal law enforcement agency under the US Department of Justice. A Department of Justice spokesperson referred​Reutersto the ​statement by the ⁠ATF.

The Cybersecurity and Infrastructure Security Agency also referred questions to the ATF.Qilin, a prolific ransomware operationthought to ​be Russian-based or Russian-speaking, posted a message on its website ​on ⁠Wednesday, in which it claimed responsibility for the compromise. The message included no description of what was stolen or how much, and did not include any ⁠samples.

Qilin ​has listed nearly 2,400 claimed attacks across more ​than 100 countries since it emerged in October 2022, ​research and tracking platform e. Crime.ch.