Details of more than 41,000 people working for the US Department of Homeland Security (DHS), including thousands of agents with Immigration and Customs Enforcement (ICE) and Customs and Border Protection (CBP), were published online on Wednesday. The leaked records include names, work addresses, phone numbers and descriptions of each person's role.
According to sources, more than 21,000 of those listed work for CBP and nearly 6,600 for ICE. The data also reveals dozens of previously unknown operation names, the agents who led them and some of the technology used in their work.
A DHS spokesperson said the department was "aware of a potential breach and is actively working to address the situation swiftly and effectively", adding: "We take all security threats against our employees and officers seriously."
A group calling itself the Department of Peace claimed it obtained the profiles through the single sign-on service Okta, and linked the hack to the conduct of immigration agents. Those who published the data said the aim was to replace "anonymity with accountability". It is the third time in recent weeks that a US government agency has been hit by a leak or hack.