A U.S. House committee that oversees defense policy is investigating the diversion of potentially sensitive F-35 fighter jet components this year from Australia to Hong Kong, a spokesperson said.

“The committee is aware of this issue and we’ve received multiple briefings on it,” said House Armed Services Committee spokesperson Heather Vaughan, adding the group is “continuing to look into the incident and conduct oversight.”

The Pentagon’s F-35 program office said in a statement that “we are aware of a shipment issue of unserviceable F-35 components and we are actively working with U.S. authorities and industry partners to retrieve these components, investigate the incident, and place safeguards to avoid a future occurrence.”