All tunnel entrances to Iran's Isfahan nuclear complex appear to have been blocked with soil, according to satellite images analyzed by the Washington-based Institute for Science and International Security (ISIS). The institute believes the moves indicate Tehran is preparing for a possible attack or invasion by the United States, Israel, or both.
According to the latest analysis, satellite images from Sunday show that two of the tunnel entrances to the Isfahan complex have been completely covered with soil, while the third entrance, the northernmost, has been equipped with additional passive protective measures. There is also no longer any vehicular activity in the area, which reinforces the assessment that the facility is “operationally closed.”
The institute, which has been monitoring Iran's nuclear facilities for years, emphasizes that covering the entrances with embankments would help absorb the force of a possible air attack and would make it more difficult for special forces to intervene from the ground in the event of a raid to seize or destroy nuclear materials, including highly enriched uranium that may be stored in the tunnels. In the same context, it is estimated that Iran may have transported sensitive materials inside the tunnels, in an attempt to protect them from possible attacks. In its analysis, the Institute for Science and International Security adds that similar preparations were last observed in the days before the US summer operations, during which the nuclear facilities in Fordow, Natanz and Isfahan were hit. It is also recalled that before the 12-day war between Israel and Iran in June, the Islamic Republic had three main active nuclear facilities.
The complex near Isfahan is known primarily for producing uranium gas, which is used in centrifuges for further enrichment. Last month, satellite images showed the construction of new roofs at the facility, which the institute said could be part of an operation to recover assets or leftover waste, although it was not clear what materials were being removed from the site. Meanwhile, US President Donald Trump has repeatedly demanded that Iran enter into negotiations for a deal on its nuclear program, warning that otherwise there could be US military intervention.
NEW: High resolution satellite imagery taken yesterday shows the extent to which Iran has covered the tunnel entrances at the Esfahan nuclear complex with soil. The middle and southern entrances are unrecognizable and fully covered in soil. The northernmost tunnel entrance which… pic.twitter.com/baYI2zCuN0
— Institute for Science (@TheGoodISIS) February 9, 2026
