A ransomware group gained access to a computer system containing information about targets of investigations by the Bureau of Alcohol, Tobacco, ​Firearms and Explosives, a spokesperson for the U.S. agency said ‌after a hacking group publicized a claimed breach on Wednesday. Tanya Roman, a spokesperson for the agency, said in an email that the standalone system was not connected to ​any other ATF systems, including case management, laboratory or eForms systems, ​which are used by the agency to manage form submissions ⁠from the public. 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.”

Full report : US federal agency confirms data breach in wake of claims by ransomware group.