This would necessarily complicate relations between Saudi Arabia and Iran, but I have to question the kind of motivations that Iran would try such an attack, let alone an attack of that kind on US soil. It would be the kind of action that would push the US to take a stronger stance against Iran, including still stronger sanctions and other actions.
MSNBC has more, including that the plot included attacks on Saudi and Israeli embassies in the US.
The criminal complaint, unsealed in federal court in New York City, identified the two alleged plotters as Manssor Arbabsiar and Gholam Shakuri.UPDATE:
Holder said Arbabsiar, who was arrested on Sept. 29 in New York, was working for the Iranian Islamic Revolutionary Guard.
Shakuri, who is based in Iran, remains at large, Holder said.
Both are originally from Iran and Arbabsiar is a naturalized U.S. citizen, the complaint said.
Saudi Arabia's ambassador is Adel Al-Jubeir, who has served in that post since 2007.
The indictment is the result of a sting operation conducted by the FBI, sources tell NBC News.
The case started when one of the suspects, who lived in Texas, made contact with an undercover DEA informant and asked for assistance from the Zetas drug cartel in Mexico to assassinate the ambassador, the sources said.
ABC News reported that Arbabsiar was the one who made contact. A source said he reportedly claimed he was being "directed by high-ranking members of the Iranian government," including a cousin who was "a member of the Iranian army but did not wear a uniform."
Arbabsiar allegedly wired $50,000 to the informant as a down payment on a $1.5 million assassination fee.
A copy of the Justice Department amended complaint can be found here. They are charged with the following:
conspiracy to murder a foreign official; conspiracy to engage in foreign travel and use of interstate and foreign commerce facilities in the commission of murder-for-hire; conspiracy to use a weapon of mass destruction (explosives); and conspiracy to commit an act of international terrorism transcending national boundaries. Arbabsiar is further charged with an additional count of foreign travel and use of interstate and foreign commerce facilities in the commission of murder-for-hire.