U.S. seeks Iran's help in finding missing American

WASHINGTON (Reuters) - In an apparent effort to test Iranian goodwill following a landmark nuclear deal, the United States on Tuesday asked Iran for help in finding an American private investigator who has been missing there for more than six years. The White House called for Iran's cooperation in locating retired Federal Bureau of Investigation agent Robert Levinson, who disappeared during a business trip to an Iranian island in the Persian Gulf in March 2007. "We welcome the assistance of our international partners in this investigation, and we respectfully ask the Government of the Islamic Republic of Iran to assist us in securing Mr. Levinson's health, welfare, and safe return," the White House said in a statement on Tuesday. In November 2010, a video surfaced in which Levinson asked for help in winning his freedom but did not say who was holding him or where. The Iranian government has repeatedly said it knows nothing about Levinson's disappearance or whereabouts. Levinson is known to suffer from diabetes, raising questions about the state of his health. But a friend of the missing man and his family said on Tuesday that there was reason to believe that Levinson was still alive. On Monday, the FBI's Washington Field Office issued a statement noting that on Tuesday, Levinson would become "one of the longest-held Americans in history," overtaking the record of 2,454 days in captivity spent by Associated Press journalist Terry Anderson in Lebanon before he was freed in 1991. The FBI said that it has been investigating Levinson's disappearance since 2007. Last year, the Bureau offered a rare $1 million reward for any information that could lead to his safe return. The latest White House plea for Iran's help comes days after world powers reached a deal with Iran to curb that nation's nuclear program in exchange for the easing some of the crippling sanctions that the global community has imposed on Tehran. Levinson, who worked for 28 years as an investigator for the FBI and the Drug Enforcement Administration, traveled on March 8, 2007 to Kish Island, a Gulf resort and free trade zone, as a private investigator. Friends of Levinson said that, around that time, he had been investigating the counterfeiting of cigarettes, though mainly in Latin America. On Kish Island, he was scheduled to meet Dawud Salahuddin, formerly known as David Belfield, an American Islamic militant, friends of Levinson say. In July 1980, during the hostage crisis in which American diplomats in Tehran were held prisoner by Iranian students, Salahuddin allegedly shot dead a former spokesman for the Shah-era Iranian Embassy at his suburban Washington home. Salahuddin then fled to Iran, where he spent the following decades pursuing activities ranging from English teaching to fighting with militants in Afghanistan to acting in an award-winning Iranian movie. Earlier this year, an Iranian lawyer for Levinson's family told the U.S.-supported broadcasting outlet Radio Free Europe that Levinson did meet with Salahuddin on Kish Island before mysteriously vanishing. In a March 2011 statement, Hillary Clinton, then secretary of State, said that Levinson was being held somewhere in South Asia, raising the possibility that he could be in the custody of a militant or criminal group. Secretary of State John Kerry met with Levinson's family in March and urged anyone with information about his whereabouts to come forward. The White House said at the time that finding Levinson is "a high priority" for the United States. (Reporting by Mark Felsenthal and Mark Hosenball; Editing by Cynthia Osterman)