John Miller, a 63-year-old British national and permanent US resident, alongside Cui Guanghai, a 43-year-old Chinese citizen, have been indicted in the United States. They face serious charges including conspiracy to smuggle sensitive American military technology to China, violations of the Arms Export Control Act, conspiracy to commit interstate stalking, and smuggling. Both men were arrested in Serbia in April and are currently detained there, potentially facing extradition to the US.

The indictment alleges that Miller and Cui solicited the procurement of various US defence articles for unlawful export to China. These items reportedly included missiles, air defence radar systems, drones, and cryptographic devices. Court documents suggest the pair discussed methods for exporting a device that could be used for encryption and decryption, and are alleged to have paid a $10,000 deposit for such equipment. They are said to have discussed with two individuals, identified in court documents as "Individual 5" and "Individual 6", how to export a cryptographic device from the US to China, considering methods such as concealing the technology within small electronics, a blender, or a motor starter.

Beyond technology smuggling, Miller and Cui are accused of orchestrating a campaign to harass and stalk an individual in the US known for criticising the Chinese government. This allegedly involved installing a tracking device on the victim's car and slashing their tires. The indictment further details plots to interfere with the victim's activities. One such plot aimed to prevent the victim from protesting Chinese President Xi Jinping's attendance at the Asia Pacific Economic Co-operation (Apec) summit in Los Angeles in November 2023. Miller and Cui were unaware that two individuals they enlisted for this purpose, identified as "Individual 1" and "Individual 2", were acting under the direction of the FBI.

Another alleged incident involved attempts to dissuade the victim from an online display of artistic statues depicting President Xi Jinping and his wife. According to the indictment, Cui and Miller paid two other individuals, identified as "Individual 3" and "Individual 4", approximately $36,000 to pressure the victim into stopping the display; these individuals were also reportedly affiliated with and acting at the direction of the FBI. Furthermore, the defendants are alleged to have bought and destroyed artistic statues created by the victim.

US officials have strongly condemned the alleged actions. Deputy Attorney General Todd Blanche described the defendants' conduct as a "blatant assault on both our national security and our democratic values," emphasizing that the Justice Department "will not tolerate foreign repression on US soil, nor will we allow hostile nations to infiltrate or exploit our defence systems." US Attorney Bill Essayli for the Central District of California stated, "The indictment alleges that Chinese foreign actors targeted a victim in our nation because he criticised the Chinese government and its president." FBI Deputy Director Dan Bongino added, “The defendants allegedly plotted to harass and interfere with an individual who criticised the actions of the People’s Republic of China while exercising their constitutionally protected free speech rights within the United States of America.”

If convicted, John Miller and Cui Guanghai face significant prison sentences. These include up to 20 years for violation of the Arms Export Control Act, up to 10 years for smuggling, up to five years for conspiracy, and up to five years for interstate stalking. The US Attorney's Office of the Central District of California noted in a statement that "An indictment is merely an allegation. All defendants are presumed innocent until proven guilty beyond a reasonable doubt in a court of law."

Both Miller and Cui remain in Serbia, with the US coordinating with Serbian officials regarding their pending extraditions. The British Foreign, Commonwealth and Development Office (FCDO) confirmed it is "providing consular assistance to a British national following his arrest in Serbia in April and are in touch with the local authorities and his family."