The U.S. defense chief’s warning follows the release this week of a report by the International Atomic Energy agency that says Iran may be carrying out secret experiments for the purpose of developing nuclear weapons.

　　The report bolstered calls by some in Israel’s government who have been calling for an attack on Iranian nuclear facilities sooner rather than later.

　　At a joint conference with Joint Chiefs of Staff Chairman General Martin Dempsey,  Panetta warned against any military action.   Panetta said he agrees with the assessment of his predecessor, Robert Gates, that a military strike would only set the Iranian nuclear program back by three years at most.

　　“You’ve got to be careful of unintended consequences here and those consequences could involve not only, not really deterring Iran from what they want to do, but more importantly it could have a serious impact in the region and it could have a serious impact on U.S. forces in the region," said Panetta.

　　Panetta said the U.S. and its allies should instead toughen economic and diplomatic sanctions on Iran to change its behavior.

　　On a visit to Israel last month,  Panetta warned against any unilateral action against Iran.  Israel says it will use military force only as a last resort.  Iran says it will retaliate if attacked.

　　Also in his remarks Thursday, Panetta called for an independent investigation of the alleged mishandling of U.S. soldiers’ remains at Dover Air Force Base in the U.S. state of Delaware, in a case that has sparked outrage among Americans. Three employees of the base’s mortuary revealed what they said were inappropriate actions that included losing body parts from the corpses of U.S. soldiers and - in one case - removing an arm bone from a dead soldier in order to make the body fit into his uniform for burial - a procedure that was reportedly done without relatives’ permission.