NEW YORK, April 14 (JTA) — Twelve Iranian Jews were arrested in Iran last month, but the specific charges remain unclear, according to sources familiar with the situation. Although Iranian authorities carried out the arrests, they apparently stem from an internal dispute between the Jewish communities of Tehran and Shiraz, in southwest Iran, according to the sources. Malcolm Hoenlein, the executive vice chairman of the Conference of Presidents of Major American Jewish Organizations, said he was in regular contact with people directly involved with the Iranian Jewish community and that efforts are under way to resolve the situation as soon as possible. Another source said he hoped the dispute could be resolved internally. The Conference of Presidents is an umbrella organization of 55 Jewish groups, which represents communal concerns to the U.S. administration. A widely distributed alert circulating on the Internet said that 23 Jews, including three rabbis, had been arrested for “teaching and learning Torah.” Hoenlein and other sources said the report was “exaggerated.” Contrary to the cyber-rumors, Hoenlein said none of the Jews arrested were facing execution. The United States government is aware of the situation, he said, but not involved in any negotiations. Some 8,000 Jews lived in Shiraz on the eve of the 1979 Iranian revolution, but today’s Jewish population there is difficult to assess. The American Jewish Year Book puts Iran’s total Jewish population at 12,500; other estimates have put the current number as high as 35,000.