Earlier this month, an F-35 Joint Strike Fighter belonging to the Japanese Air Self-Defense Force went down over the Pacific during a training flight. Three other F-35s participating in the flight returned home safely, with the pilot and much of the missing F-35’s wreckage, still missing.

“The Japanese have the lead there, and we’re working very collaboratively with them,” acting Defense Secretary Patrick Shanahan said Friday. “And we’ve got a capability if what they have doesn’t prove to be sufficient.”

Search efforts remain underway for the remains of the aircraft and its ill-fated pilot, prompting many to worry about the chances Russian or Chinese recovery efforts, assumed to be underway covertly, may find large components from the aircraft before Japanese and American teams. Such a covert recovery could cause a number of problems for the fighter or for American and Japanese interests in the Pacific. Both China and Russia are in the process of fielding their own troubled fifth-generation fighters, with China in dire need of an effective engine for its J-20 and Russia still struggling with developing sufficient stealth technology. Getting their hands on large portions of a downed F-35 could certainly aid in either, or both, efforts.

“This is a very important aircraft, so we would like to locate the aircraft as soon as we can and salvage it,” Japanese Defense Minister Takeshi Iwaya said through an interpreter on Friday. “Japan will lead the investigation, but we’re hoping and also it is indispensable to have the support of the U.S. So while we do that, we would like to find the root cause of the accident.”