Iran executed a nuclear scientist convicted of spying for the United States, an official said Sunday, acknowledging for the first time that the nation secretly detained and tried a man who was once heralded as a hero. Shahram Amiri defected to the U.S. at the height of Western efforts to thwart Iran's nuclear program. When he returned in 2010, he was welcomed with flowers by government leaders and even went on the Iranian talk-show circuit. Then he mysteriously disappeared. He was hanged the same week that Tehran executed a group of militants, a year after Iran agreed to a landmark accord to limit uranium enrichment in exchange for the lifting of economic sanctions.FILE--In this file photo...
