A Washington-based Lebanese citizen, who went missing in Tehran in September, is an American spy, Iranian state television claimed Tuesday, according to media reports. The man, identified as Nizar Zakka, has been arrested by Iranian authorities.

"Nizar Zakka has deep ties to the U.S. intelligence and military establishment," state broadcaster IRIB quoted an unnamed source as saying, according to Reuters.

Zakka’s family said through their lawyer that they were "shocked by these false accusations." They also stressed that the IT expert has no "relation with any military, security institution or secret services whatsoever."

Zakka went missing on Sept. 18 while visiting Tehran for a state-sponsored conference, the Associated Press (AP) reported. He was last seen leaving his hotel in a taxi for the airport to travel to Beirut, but he never boarded the plane, Lebanese lawyer Antoine Abou Dib, reportedly wrote in a statement last week.

Following Zakka’s disappearance, his family reportedly urged Lebanese authorities "to work seriously on determining the whereabouts of Mr. Zakka and bring him safely back to his country Lebanon."

The news comes as Iran's Intelligence Minister Mahmoud Alavi said Monday that the ministry had been discussing ways to combat foreign influence in the country as Tehran has struck a nuclear deal with world powers, and open Iran to foreign businesses.