Fearing a Ground Invasion, Iran Seals Off Isfahan Nuclear Tunnels

New high-resolution imagery from ISIS reveals a deliberate "lockdown" at Iran’s Isfahan facility. Following the burial of tunnel entrances in February, Iranian forces have now added roadblocks and earth berms to deter ground raids on its 60% enriched uranium stockpile.

 

According to an analysis released yesterday (April 9, 2026) by the Institute for Science and International Security (ISIS), images taken on April 8 reveal makeshift roadblocks and added physical barriers now installed directly in front of all three tunnel entrances. These include earth berms, debris, fencing, and other obstacles specifically designed to slow or prevent ground access.

The entrances themselves were already completely buried with soil back in February. ISIS assesses this is not preparation to reopen the site for operations, but rather a deliberate lockdown to protect it against potential airstrikes or special-forces raids.

Key context (per IAEA and ISIS):

* The Isfahan tunnels are believed to hold a significant portion of Iran’s stockpile of 60% enriched uranium, material that could be further processed into fuel for multiple nuclear weapons.

* Vehicle activity, checkpoints, and security equipment remain visible on site, signaling tight ongoing control by Iranian forces.

This latest move comes as regional tensions remain high and the Isfahancomplex continues to be viewed by Tehran as a highly sensitive target. (Source)