WASHINGTON (Sputnik) — The Russian consulate in San Francisco is working on the issue.
"I would not jump to the conclusion that they are Russian citizens," Petrov stated. "We are going to clarify [that]."
The consul general noted that the Russian side has not received any official notifications about the arrest from the American authorities.
Earlier on Thursday, the FBI arrested Syed Raheel Farook, a brother of one of the San Bernardino shooters, his wife Tatiana Farook and her sister Mariya Chernykh, both originally from Russia.
Mariya has been married to Enrique Marquez, who bought weapons used in the San Bernardino terrorist attack. In 2015, the US authorities accused Marques of receiving money for marrying the woman, who lived separately in Ontario.
At present, Mariya faces 25 years in prison for marriage fraud, while the Farooks could spend five years in jail for aiding her, according to the US Justice Department.