The FBI and the DEA have disrupted a plot involving Iran to commit terrorism inside the United States, a senior U.S. official told CNN Tuesday. The official said the alleged plan was directed by elements of the Iranian government and involved a plot to kill the Saudi ambassador to the United States.

http://news.blogs.cnn.com/2011/10/11...ran/?hpt=hp_t1

Link to the pdf file with the Justice Department complaint.