Which federal agency initiated investigations into property damage reports following the Starship flight anomaly?

The Federal Aviation Administration (FAA)

The consequence of confirmed debris landing on inhabited islands automatically triggers official oversight by the responsible regulatory body. After the specific test flight where debris fell onto the islands, the Federal Aviation Administration (FAA) was responsible for initiating investigations into the reported instances of property damage. Furthermore, the FAA’s authority extended to issuing ground stops affecting multiple airports in the region due to the resulting airspace contamination. This regulatory response demonstrates the broad impact of such incidents, extending beyond immediate physical fallout to encompass air traffic management and safety protocols surrounding the test area, all coordinated under the FAA's purview.