On Wednesday, October 10, the U.S. Justice Department announced that a Chinese citizen indicted on espionage charges had been taken into custody in Belgium, and will soon be extradited to the United States to face trial.

“This unprecedented extradition of a Chinese intelligence officer exposes the Chinese government’s direct oversight of economic espionage against the United States,” said Bill Priestap, the FBI’s assistant director for counterintelligence.

Yanjun Xu, an officer within China’s Ministry of State Security (MSS), has been charged with attempting to steal secrets pertaining to American military aircraft from a number of defense contractors. China has a long history of stealing aviation technology to bolster their military initiatives, primarily from Russia and the United States. Another Chinese national, Su Bin, is currently serving a 46-month sentence in federal prison for stealing the plans for Lockheed Martin’s F-22 Raptor and F-35 Joint Strike Fighter, both of which are considered to be among the most advanced fighter platforms on the globe. Since then, China has began production on an F-22 copy, dubbed the J-20, with development still underway on the forthcoming J-31, a copy of the F-35.

Yanjun Xu’s extradition from Belgium marks the first time a spy with a formal affiliation with the Chinese government has ever been returned to the United States to stand trial, and the Justice Department’s announcement comes amid a period of heightened tensions between the United States and China. Trade disputes, exacerbated by military confrontations in the hotly contested South China Sea, have fueled a rapid decline in U.S./China relations. President Trump recently accused China of attempting to influence the upcoming 2018 midterm elections. Vice President Mike Pence soon followed up those allegations with more of his own, calling out China for the “wholesale theft of American technology.”