US Homeland Security investigates breach of government information network
The department is called to "thoroughly investigate" who is behind the breach.

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- US Department of Homeland Security is investigating a cyber breach in a government information-sharing network.
- The affected system reportedly shared sensitive but unclassified data with foreign law enforcement and local authorities.
- GovExec reports the breach may have occurred between late May and early June. Officials have not confirmed details or identified attackers.
Key Takeaways by nexos.ai, reviewed by Cybernews staff.
The Department of Homeland Security (DHS) said on Thursday it was investigating a breach in an unnamed information-sharing network.
In a statement, DHS said there had been a "recent cyber incident" involving an "unclassified legacy information sharing environment" but did not provide further details and did not respond to follow-up questions.
GovExec, which first reported the news, said the breach affected the Homeland Security Information Network, a platform used to share sensitive but unclassified data with partners, including foreign law enforcement, local authorities, and other organizations. GovExec, which cited two unnamed sources familiar with the matter, said the breach was believed to have occurred between late May and early June.
US Senator Mark Warner, the top Democrat on the Senate Intelligence Committee, said the information carried in the network, "while not classified, is highly sensitive, and its exposure risks national security."
He called on DHS and the Justice Department to "thoroughly investigate" who breached the network and what they compromised.