MOSCOW (AP) — Jailed Wall Street Journal reporter Evan Gershkovich has been charged with espionage in Russia and has entered a formal denial, two Russian news agencies reported Friday.

The state news agency Tass and the Interfax news agency said a law enforcement source informed them that Russia’s Federal Security Service, known as the FSB, had officially charged the American journalist.

The news outlets didn’t say in what form Gershkovich was formally charged or when it happened, but generally suspects are presented a paper outlining the accusations.

In the Russian legal system, the filing of charges and a response from the accused represents the formal start of a criminal probe, initiating what could be a long and secretive Russian judicial process. .

Tass quoted its source as saying: “The FSB investigation charged Gershkovich with espionage in the interests of his country. He categorically denied all accusations and stated that he was engaged in journalistic activities in Russia.”

The source declined further comment because the case is considered secret.

Russian authorities arrested Gershkovich, 31, in Yekaterinburg, Russia’s fourth-largest city, on March 29. He is the first US correspondent since the Cold War to be detained for alleged spying.

The FSB specifically accused Gershkovich of trying to obtain classified information about a Russian arms factory. The Wall Street Journal has denied the accusations.

The case has caused an international uproar. On Thursday, the US ambassador to Russia and a top Russian diplomat met to discuss it.

In the meeting with US Ambassador Lynne T Tracy, Russian Deputy Foreign Minister Sergei Ryabkov stressed “the serious nature of the charges” against Gershkovich, according to a Russian Foreign Ministry statement.

The statement repeated earlier Russian claims that the reporter “was caught red-handed while trying to obtain secret information, using his journalistic status as a cover for illegal actions.”

Lawyers representing Gershkovich met with him Tuesday for the first time since his detention, according to Wall Street Journal. Editor-in-Chief Emma Tucker.

Tucker said the reporter is in good health and “is grateful for the outpouring of support from around the world. We continue to call for his immediate release.”

Gershkovich was ordered held behind bars for two months in Russia pending an investigation. A Moscow court said Monday that it had received a defense appeal of his arrest; the appeal is scheduled to be heard on April 18, Russian news agencies reported.