The Pentagon said it had no knowledge of a U.S. military aircraft landing in Iran after the Persian Gulf country's state-run Fars news agency said an American plane was forced to land following an airspace violation.

State-owned Al-Alam television cited an unidentified senior Iranian official as saying the aircraft belonged to a European aid agency. The aircraft was Hungarian and no Americans were aboard, Sky News said, citing Iranian television.

"We have no reports of U.S. military aircraft landing in Iran," said Lieutenant Colonel Patrick Ryder at the Defense Department, citing operations of the U.S. Central Command, whose jurisdiction includes Iran. He said the Pentagon was checking reports further.

Central Command spokesman Lieutenant Commander William Speaks called the Iranian report "bogus."

"We have absolutely no information of any U.S. military aircraft landing in Iran—not today, not yesterday. It's a bogus report."

White House National Security spokesman Gordon Johndroe said, "We're looking into the various and conflicting reports coming from the Iranian 'news' agencies, but do not have any information at this time that would lead us to believe they are correct."

State Department spokesman Robert Wood said in an e-mail, "We've just seen the reports and are looking into the matter."

Fars said the plane was carrying five U.S. generals and three non-military passengers. The news agency said the plane's occupants were questioned before being released and allowed to leave for Afghanistan, their original destination.