Freelance journalist Rajeev Sharma, who was arrested by the Special Cell of Delhi Police under the Official Secrets Act, is accused of passing sensitive information to Chinese intelligence, police said on Saturday.
According to the police, a Chinese woman and her Nepalese associate were also arrested for paying him large amounts of money routed through shell companies.
Sharma was produced before the court on September 15, which sent him to six-day police custody.
Delhi Police Special Cell said Sharma, a resident of Pitampura in New Delhi, was "found to be in possession of some defence-related classified documents".
The police said his bail application is listed for September 22.