The Department of Homeland Security is investigating a breach of its Homeland Security Information Network (HSIN), which allows government agencies and local officials to share intelligence, following reports that hackers broke into servers during late May and early June.

Sen. Mark Warner warns that the exposure risks national security, as HSIN supports major events like the current World Cup in the US and was used last year for emergency response.

DHS spokespersons stated they immediately isolated affected systems, mitigated vulnerabilities, and launched a comprehensive investigation. However, details on stolen data remain unclear.

This incident comes amid ongoing cybersecurity challenges for federal agencies, including major breaches under the Trump administration, highlighting the ever-evolving threat landscape.