An Iranian graduate student of the University of Texas went on trial Tuesday in Tehran on charges of "relations with a hostile country," his lawyer said.
Saeed Khalili said his client, Omid Kokabee, pleaded not guilty to the charges against him at the opening session of his trial. He is also charged with receiving "illegitimate funds."
"He denied all charges," said the lawyer Khalili, adding that the entire session was devoted to procedural matters. He said the court is to hold another session, though no date has been set.
Based on the charges, the court can sentence Kokabee to up to 10 years in jail.
Iranian authorities arrested the 29-year-old Kokabee in February at Tehran's international airport as he was returning to the U.S. after a short break in Iran.
He was studying optics in the physics department of the University of Texas.
Khalili told The Associated Press that he was not able to speak with Kokabee at the trial session.
Though Iran and the United States do not have diplomatic relations, many Iranian students apply to study in the U.S. every year.