The Wall Street Journal, in an exclusive report, said Israeli intelligence agencies believe the Islamic Republic moved thousands of uranium enrichment centrifuges last fall to deep tunnels inside “Kuh-e Kelang,” near the Natanz facilities.

This relocation followed the June 2025 airstrikes on the Islamic Republic’s nuclear sites. Based on satellite images, this granite fortress was excavated 90 to 137 meters underground, making it much harder for bunker-buster bombs to penetrate.

The International Atomic Energy Agency has said it has no permission to inspect this site.

Donald Trump has also recently referred to this underground complex as a possible military target.