Sensitive F-35 fighter jet components bound for the United States were unexpectedly diverted to Hong Kong this summer, prompting a congressional inquiry and concerns that China could gain access to classified military technology.

Axar.az reports, citing Politico, that the shipment was being transported from Australia for repairs when it was rerouted across the Pacific, according to three people familiar with the matter. The Pentagon confirmed that some components went missing.

The shipment, handled by an intermediary for F-35 manufacturer Lockheed Martin, included an F-35 canopy containing stealth technology. Experts said possession of the component could allow an adversary to study or potentially reverse-engineer aspects of the aircraft’s technology.

The F-35 Joint Program Office said it was working with US authorities and industry partners to recover the components and investigate the incident.

The diversion triggered briefings for congressional staff, with the first held in June and further briefings expected. The State Department declined to comment, while the Chinese Embassy said it was not aware of the incident.

The incident has also renewed scrutiny of the F-35 supply chain. A 2023 Government Accountability Office report found that more than 1 million F-35 spare parts had gone missing over five years, with the Pentagon unable to fully track losses worth tens of millions of dollars.