The judge has been heading an independent inquiry into the July 10 death of Zahra Kazemi, a Canadian of Iranian origin, who died three weeks after she was detained for taking photographs outside a Tehran prison during student-led protests.
The judge, Javad Esmaeili, charged the Intelligence Ministry agent with "semi pre-meditated murder." There was no immediate explanation of the charge.
The agent was one of two ministry officials charged earlier over Kazemi's death. But the prosecutor's office rejected the charges Sept. 1 and called for further investigations.
The charges against the second agent were dismissed, according to a statement released Monday by the prosecutor's office.
"The crime is attributed to one of the (Intelligence Ministry) interrogators and the reasons have been presented in the law suit against the accused," according to the statement issued by the prosecutor's office on the charges set by the judge.
The statement said the judge concluded that no government body was behind the crime.
After her arrest, the 54-year-old Kazemi was interrogated for 77 hours. She was then rushed to a hospital's intensive care unit, where she died 14 days later.
Initially, the hard-line Tehran prosecutor, Saeed Mortazavi, was quoted as saying Kazemi had died of a stroke. But a presidential-appointed committee discredited this version and found that she had died of head injuries sustained while in custody.
Canada has complained to Iran over the earlier handling of Kazemi's case, threatened sanctions and withdrew its ambassador after the photojournalist's body was buried in her birthplace, the southern Iranian city of Shiraz, against the wishes of Canadian authorities and her son, who lives in Montreal.
According to the Committee to Protect Journalists, the Iranian government's explanations for the death have shifted several times. After first blaming a stroke, vice president Mohammad Ali Abtahi said Kazemi died from a "brain hemorrhage resulting from beatings." But then Foreign Minister Kamal Kharrazi said it might have been an accident.