Operation Southern Guard (OSG)

What We Did:

We are pleased to present this Lead Inspector General (Lead IG) report to Congress on Operation Southern Guard (OSG). This report fulfills our quarterly reporting responsibilities pursuant to the Inspector General Act of 1978, as amended.

In January 2025, President Donald J. Trump issued a series of actions and executive orders, declaring a national emergency at the southern U.S. border and directing the Department of War (DoW) and the Department of Homeland Security (DHS) to expand the illegal alien holding capabilities and facilities at Naval Station Guantánamo Bay (NSGB) to full capacity. The OSG mission is for the DoW to provide support for DHS-led efforts to hold illegal aliens at NSGB.

On March 28, 2025, the DoW designated OSG as an overseas contingency operation, triggering Lead IG reporting responsibilities under 5 U.S.C. 419. The Council of the Inspectors General on Integrity and Efficiency designated the DoW IG as the Lead IG for OSG, effective July 14, 2025.

This report describes the activities of the U.S. Government in support of OSG, specifically, DoW support to the DHS in the processing, detention, housing, and all aspects of illegal alien holding operations at NSGB, during the period of January 1 to March 31, 2026. This report also discusses the planned, ongoing, and completed oversight work conducted by the DoW OIG, State OIG, the DHS OIG, and our partner oversight agencies.