The U.S. lost one of its most advanced surveillance drones on a C.I.A. mission in Iran, unnamed "U.S. officials" said on Monday, which means Tehran now likely possesses the stealth aircraft. Little is known about the Lockheed-designed aircraft, and The Los Angeles Times says "the Pentagon has not revealed its price tag, size or top speed. But it has acknowledged this: The Sentinel may now be in Iranian hands." U.S. intelligence used the "jet-powered, bat-winged RQ-170 Sentinel drone" to perform surveillance on Osama bin Laden's compound last spring, which tells you something about how prized it is. The Pentagon certainly doesn't want its military secrets getting to Iran, but according to one expert The Times interviewed, the larger worry is that Tehran will sell them far and wide. "It carries a variety of systems that wouldn't be much of a benefit to Iran, but to its allies such as China and Russia, it's a potential gold mine," Peter W. Singer, author of Wired for War, told the paper. The U.S. military first said it had lost a drone that was flying over western Afghanistan, but The Times suggested it may have strayed into Iran airspace by mistake. Sources told CNN, however, that they believed the drone went down in Afghanistan before Iran recovered it. "They did not believe the mission involved flying the drone directly over Iran because the reconnaissance capability of the-RQ 170 drone allows it to gather information from inside Iran while remaining on the Afghanistan side of the border." Either way, it's a big intelligence coup for Tehran and a real fumble for the Pentagon and Central Intelligence Agency.