Two retired members of the French secret services are suspected of being double agents for an unnamed foreign power, France's defense ministry said.
The ministry said in a statement released late Thursday the two men have been brought before an investigating judge over suspicion of "treason through delivering information to a foreign power" and "compromising the secrecy of national defense."
The ministry did not specify for which country the agents are suspected to have worked. It mentions "very serious actions" detected by France's foreign intelligence agency DGSE, without other details.
The ministry said the wife of one of the men is also suspected to be involved.
Defense minister Florence Parly, speaking on CNews television, said their actions could "potentially compromise state security."
Le Monde newspaper reports the two were arrested in December and have been detained since then.
News and entertainment show Quotidien, which first reported the news on TMC television Thursday night, reported without citing sources that the agents were working for China and that one of them was based in Beijing.
French authorities declined comment on the report.