Confirmed: Iran Enriching Uranium Underground Higher level of enrichment at Fordo prompts international concern By Matt Cantor, Newser User Posted Jan 9, 2012 7:43 AM CST Updated Jan 9, 2012 7:56 AM CST 18 comments Comments Iranian President Mahmoud Ahmadinejad, center, visits the Natanz Uranium Enrichment Facility some 200 miles south of the capital Tehran, in this 2008 file photo. (AP Photo/Iranian President's Office, File) (Newser) – Iran's claim has been confirmed: The country has indeed begun enriching uranium at an underground bunker, two diplomats tell the AP today. They call the news particularly worrying because the Fordo site is being used to make material that can be upgraded more quickly and easily for use in a nuclear weapon than the nation's main enriched stockpile. The anonymous diplomats, whose info comes from an inspection of Fordo last week by the International Atomic Energy Agency, say that centrifuges at the Fordo facility are churning out uranium enriched to 20%, compared to the 3.5% being made at Iran's main enrichment plant. Tehran had announced months ago that it would use the Fordo facility for 20% production, saying it needs the higher grade material to produce fuel for a Tehran reactor that makes medical radioisotopes for cancer patients. But the start of the operation increases international fears that Iran is determined to move closer to the ability to make nuclear warheads. Boosting concerns even more: Fordo's location. The facility is a hardened tunnel protected by air defense missile batteries and the Revolutionary Guard. According to semiofficial media, Iran's nuclear chief recently said "the enemy doesn't have the ability to damage it."