Tehran announced Tuesday that they had custody of Rigi, who was arrested on a flight from Dubai to Kyrgyzstan. Rigi led the Sunni militant group Jundallah, which claimed responsibility for an October attack in southern Iran that left several members of the Iran Revolutionary Guard Corps dead.
Pentagon spokesman Geoff Morrell said Iranian allegations that Rigi had ties with U.S. officials were incorrect. Iranian intelligence officials said Rigi was at a U.S. base in Afghanistan the day before his arrest.
"Iranian claims that Abdolmalek Rigi was at a U.S. military installation prior to being apprehended are absolutely false," said Morrell.
Tehran paraded Rigi before television cameras Thursday, where he told state-funded broadcaster Press TV that he had the support of U.S. officials in Afghanistan.
"They said they would cooperate with us and will give me military equipment, arms and machine guns," he said. "They also promised to give us a base along the border with Afghanistan next to Iran."
Jundallah is not included in the U.S. list of terrorist organizations.