Dubai, Jul 17 (AP) A Chinese-American graduate student sentenced to 10 years in prison in Iran for allegedly “infiltrating” the country and sending confidential material abroad is innocent of all charges against him, his advising professor at Princeton University said today.

Xiyue Wang’s arrest, which authorities said happened nearly a year ago, only came to light a day earlier when Iran’s judiciary announced his sentence as well as the detention of President Hassan Rouhani’s brother in an unrelated case.

Princeton said that it is “very distressed” by the charges leveled against Wang while he was carrying out scholarly research in the Islamic Republic. It has been working Wang’s family, the U.S. government, lawyers and others to secure his release, it added.

“His family and the university are distressed at his continued imprisonment and are hopeful that he will be released after his case is heard by the appellate authorities in Tehran,” the university said.

An article posted on Mizan Online, a website affiliated with the judiciary, said 37-year-old Wang was born in Beijing and entered Iran as a researcher who is fluent in Persian. It said he is a dual national of the United States and China.

He has already filed an appeal to his sentence, according to the website.

Wang was arrested on August 8, 2016 and is accused of passing confidential information about Iran to the US State Department, Princeton’s Sharmin and Bijan Mossavar-Rahmani Center for Iran and Persian Gulf Studies, the Harvard Kennedy School and the British Institute of Persian Studies, Mizan Online said.

It alleged he recorded some 4,500 pages of digital documents, paid thousands of dollars to access archives he needed and sought access to confidential areas of Tehran libraries.

Princeton University professor Stephen Kotkin, who has served as Wang’s doctoral adviser, defended him in an email to The Associated Press.

“Xiyue Wang is a remarkable, linguistically gifted graduate student,” he wrote. “He is innocent of all the charges.”

The documents Wang collected were 100 years old, Kotkin said, adding that Wang “has told me often of his exhilaration at the exquisiteness and depth of Persian civilization.” In its statement, Princeton said Wang was arrested while conducting research on the 1794-1925 Qajar dynasty for his doctorate in late 19th and early 20th century Eurasian history.

A photo of Wang on Princeton’s history department shows him posing under a plaque at the entrance of China’s official Xinhua News Agency’s bureau in Kabul, Afghanistan.(AP) AMS

This is published unedited from the PTI feed.