Ireland opened the investigation six months ago after the U.S. Federal Bureau of Investigation smashed a Russian spy ring involving 11 men and women posing as American civilians. Several were found to have used Irish passports as part of their travels to and from Russia and other countries.
The Department of Foreign Affairs in Dublin announced that police have concluded that Russian agents stole the personal details of six real Irish citizens and used them to counterfeit Irish passports.
The U.S. expelled all 11 spies to Russia in July. Most of them had been living in the U.S. since the 1990s and had instructions to work their way into influential business and political circles, but they largely failed in that mission. Their fabricated identities included surnames common in Ireland, including Murphy and Foley.
In a statement it said the ambassador was told "that the activities of Russian intelligence services in connection with the forgery of Irish passports and the effective theft of the identity of six Irish citizens are completely unacceptable and not the behavior the (Irish) government would expect from a country with which we have friendly relations."
It declined to identify the Russian embassy official being expelled as punishment, or to specify whether the official was directly linked to the theft or counterfeiting efforts.
"It is regrettable that this action has been necessary. However, the primary responsibility of the government is to ensure the security and well being of Irish citizens, which includes protection of the integrity of Irish passports," the statement said.