An alleged plot to send anti-aircraft missiles and guns to Syria or Iran was thwarted after a key figure was arrested in Philadelphia, the FBI said in documents released Monday. -snip- He was after missiles that could "take down an F-16," the affidavit says. Little did Tarraf know, he was requesting the weapons from an undercover agent, according to documents. The affidavit alleges that Tarraf paid a $20,000 cash deposit to the agent in July for machine guns and shoulder-fired Stinger missiles, MyFoxPhilly.com reported. The documents say Tarraf's dealings with the undercover officer date back to June 2007. -snip-