A US Army analyst has been arrested and charged with selling sensitive military secrets to a contact in China.
Sgt Korbein Schultz was arrested on Thursday at Fort Campbell in Kentucky following an inquiry by the FBI and US Army counterintelligence.
According to the charges, he was paid $42,000 (£33,000) in exchange for dozens of sensitive security records.
Officials say the criminal conspiracy began in June 2022 and continued up until his arrest.
Sgt Schultz is charged with conspiracy to obtain and disclose national defence information, exporting technical data related to defence articles without a licence, conspiracy to export defence articles without a licence, and bribery of a public official.
It is unclear if he has hired an attorney who can comment on the charges against him.
"The conduct alleged in today's indictment represents a grave betrayal of the oath sworn to defend our country," said Larissa Knapp of the FBI's National Security Branch.
"Instead of safeguarding national defence information, the defendant conspired with a foreign national to sell it, potentially endangering our national security."
The confidential documents were provided to a contact that the defendant believed to be living in Hong Kong, officials say.
Some of the information he allegedly provided related to hypersonic equipment, studies on the future development of US military forces, and a document on China's military preparedness.
The justice department charging documents do not name the Chinese government as implicated in the scheme, or identify the contact who paid him.
The indictment said he was instructed to transmit "original and exclusive documents" to his contact.
The intelligence he provided includes information related to Russia's war in Ukraine and the "operability of sensitive US military systems and their capabilities".
It also included US plans regarding Taiwan in the event it should come under attack.
Messages sent by Sgt Schultz include one where he says he "wished he could be 'Jason Bourne'," the indictment says, in reference to the fictional spy character.
After being promised more money from his handler, he said in another message: "I hope so! I need to get my other BMW back!"
Earlier this week, investigators arrested a retired US Army colonel in Nebraska who is accused of sending classified information to a person through a foreign dating website.
The arrest of the retired colonel came just hours after a US airman from the Massachusetts Air National Guard pleaded guilty to six counts of illegally retaining and transmitting national defence information.