TEHRAN, Iran — The mother of detained Washington Post correspondent Jason Rezaian said Monday that Iran has charged her son for simply "reporting on a country that he loves," as he addressed the judge overseeing his closed-door espionage trial.

Details of Rezaian's second court hearing remained vague in Iranian media accounts, although the semi-official Tasnim news agency said the 39-year-old bureau chief defended himself in English. The agency said a translator later handed Judge Abolghassem Salavati a transcript of Rezaian's remarks in Persian.

Rezaian faces charges including espionage and propaganda against the Islamic Republic, which the Post has said carry 10 to 20 years in prison if he is convicted. U.S. officials, the Post and rights groups have strongly criticized Rezaian's trial, demanding he be freed.

Rezaian's detention of over 300 days and his trial come as Iran negotiates with world powers over its contested nuclear program, leading many, including his mother, Mary, to suggest current events may play a role in his case.

"Someone believes that there is an advantage to holding him," Mary Rezaian told The Associated Press outside her son's hearing at Tehran's Revolutionary Court. "Personally, I do not think so."

Standing next to his wife, Yeganeh Salehi, Mary Rezaian said her son is "very tired, very distressed." She also said she didn't know how many more court hearings will be held or how the trial is going. Both she and Rezaian's wife have not been allowed to attend the hearings, although Mary Rezaian has seen him twice briefly since she arrived in Iran a month ago.

"He is being accused of being a master spy when all he was doing was reporting on a country that he loves. So it is very hard for him. Very, very hard for him. And of course he misses his wife," Mary Rezaian said. "So two years they have been married, one year he has been in prison. It is a very, very difficult thing."

Salehi declined to discuss her husband's trial, only saying: "I am not in a good state."

Rezaian, his wife and two photojournalists were detained July 22, 2014, in Tehran. All were later released except Rezaian. At the hearing Monday, two other people detained with Rezaian were in court, according to Iran's official IRNA news agency, without elaborating or identifying them.

Rezaian's defense lawyer, Leila Ahsan, previously said that Salehi and one of the two unidentified photojournalists also would stand trial. Ahsan did not immediately return calls for comment Monday.

As in the May hearing, reporters gathered in front of the courthouse gate did not see Rezaian, his lawyer or the other two co-defendants. Authorities usually bring those charged in sensitive cases into the building through a gate closed to the public.

Rezaian is a dual U.S.-Iranian citizen who was born and spent most of his life in the United States. Iran does not recognize other nationalities for its citizens.

Salehi, a reporter for The National newspaper in Abu Dhabi, remains in Iran, barred from traveling abroad, the Post has said.

At Rezaian's first hearing, the court alleged that Rezaian had written to U.S. President Barack Obama and also cited a trip he made to the U.S. Consulate in Dubai, Iran's semi-official Mehr news agency reported at the time.

Martin Baron, the Post's executive editor, has disputed the alleged correspondence, saying that Rezaian did not write to the president but merely filled out an online job application for the Obama administration after the 2008 election, a position for which he was never hired. Rezaian's brother, Ali, said that Jason had visited the consulate in Dubai, but the only reason was to obtain a U.S. visa for his wife.