Satellite imagery shows evidence that Iran took steps to seal off its nuclear enrichment facility at Fordow in the days leading up to the U.S. strikes, which would have shielded it against a potential ground raid. This raises an additional question about whether this may have factored into the final decision to launch Operation Midnight Hammer, with B-2 stealth bombers carrying 30,000-pound GBU-57/B Massive Ordnance Penetrator (MOP) bunker buster bombs being seen as the remaining viable option for attacking the facility conventionally.
Readers can first get up to speed with what is known about Operation Midnight Hammer, which targeted Iranian nuclear facilities at Isfahan and Natanz in addition to Fordow on the night of June 21-22, in our past reporting here.
As news of the U.S. strikes on Iran over the weekend was still unfolding, commercial satellite imagery provider Maxar Technologies released a set of images of Fordow taken on June 19 and 20, along with the following statement:
“Prior to tonight’s airstrikes on the three Iranian nuclear-associated facilities, Maxar collected high-resolution satellite imagery on June 19th and June 20th of the Fordow fuel enrichment facility that revealed unusual truck and vehicular activity near the entrance to the underground military complex. On June 19th, a group of 16 cargo trucks were positioned along the access road that leads to the tunnel entrance of the facility. Subsequent imagery on June 20th revealed that most of the trucks had repositioned approximately one kilometer northwest along the access road; however, additional trucks and several bulldozers were seen near the entrance to the main facility and one truck was positioned immediately next to the main tunnel entrance.”
Maxar’s release had, in turn, quickly prompted widespread speculation that the images showed Iranian efforts to move nuclear material, sensitive equipment, and/or other items of interest from Fordow ahead of a potential operation to destroy it. Though this does not look to be what is visible in the imagery, it still remains a possibility, in general. TWZ had noted in prior reporting on the Israel-Iran conflict that the regime in Tehran could move to disperse its stockpile of uranium and other aspects of its nuclear program, including critical refining hardware, amid escalating threats, if it had not done so already.
All this being said, there are multiple indicators that what Maxar’s imagery really shows is Iranian personnel sealing up entrances to Fordow as part of efforts to shield the facility against a ground raid. This is something TWZ‘s Tyler Rogoway explicitly raised the possibility of yesterday.
For one, the vehicles seen in the images are predominantly dump trucks, which is not what one would expect to see if the activity was centered on moving sensitive nuclear material and industrial equipment to other locations. The clear presence of bulldozers and/or front-end loaders only further points to earth-moving activities, the exact kind that would be needed to close up the tunnels.
A comparison of the pre-strike imagery from Maxar with post-strike images that the company subsequently released shows Fordow’s entrances fully packed with dirt following Operation Midnight Hammer. In addition, at least some of the dirt looks to be ejected, further suggesting that the Iranians had filled the entry points on purpose beforehand.
For years, TWZ has noted that Israel lacks the means, at least that we know of, to prosecute deeply buried targets like Fordow conventionally except through ground raids. Well before Operation Midnight Hammer was launched, it had been established that GBU-57/B MOP-armed B-2 stealth bombers presented the only readily available conventional option for striking the deeply-buried heart of the facility at Fordow short of putting boots on the ground.
“A U.S. official said the Israelis told the Trump administration that while they may not be able to reach deep enough into the mountain [under which Fordow is situated] with bombs, they may ‘do it with humans,'” Axios had reported on June 18, a day before Maxar noticed the unusual vehicle activity at the facility.
Sealing Fordow against the threat of a ground raid would have made additional sense for Iranian authorities given that Israel was steadily gaining air superiority and increasing its general aerial presence further and further east into Iran. This would have been important for enabling a major Israeli commando operation using a combination of helicopters and fixed-wing aircraft, which would have still been highly risky.
Israel had already employed teams of operatives inside their country in the opening phase of the current conflict. The IDF had also demonstrated an ability and willingness to carry out complex ground raids on underground facilities when it destroyed a missile factory in Syria last year. TWZ noted at the time that the raid, which targeted a facility that had been built with support from the regime in Tehran in the first place, had sent a clear message to the Iranians.
Furthermore, similar vehicle activity was also notably observed at Isfahan on June 20 in a satellite image from Airbus Defense & Space, which points to a broader Iranian effort to seal nuclear facilities last week. Clearly buried tunnel entrances also appeared there in imagery from after the U.S. strikes this weekend, raising the same questions about whether or not they had been filled in beforehand.
As noted, there is a question then about whether Iran taking the ground raid option off the table by sealing the entrances to Fordow and Isfahan actually helped fuel the ultimate decision to launch Operation Midnight Hammer. B-2 bombers dropped 12 MOPs on Fordow, and another two on an underground facility at Natanz, in the course of the mission. A barrage of more than two dozen Tomahawk cruise missiles struck above-ground targets at Isfahan.
Overall, a clear picture of the full extent of the damage from the U.S. strikes on Fordow, as well as Isfahan and Natanz, has yet to emerge.
“The battle damage assessment is ongoing, but our initial assessment, as the chairman said, is that all of our precision munitions struck where we wanted them to strike and had the desired effect,” U.S. Secretary of Defense Pete Hegseth had told TWZ and other outlets at a press conference yesterday. This “means especially in Fordow, which was the primary target here, we believe we achieved destruction of capabilities there.”
Earlier today, the Israel Defense Forces (IDF) also said that they “struck routes in order to obstruct access to the Fordow enrichment site,” but has yet to elaborate.
If Iran had already sealed the entrances to Fordow, (as well as Isfahan), coupled with the new Israeli strikes today, it could also be more difficult for any actor to quickly assess the damage, overtly or covertly. Sealing the entry points could have helped contain any radioactive and other contamination. Sealing off those sites could also point to nuclear material and other sensitive equipment still being contained therein, even if Iran has taken some steps to disperse elements of its nuclear program.
In a separate series of tweets following Rogoway’s posts on X yesterday, Jeffrey Lewis, head of the East Asia Nonproliferation Program at the James Martin Center for Nonproliferation Studies at the Middlebury Institute of International Studies at Monterey, said he also assessed that the available satellite imagery showed Iran sealed the entrances at Fordow prior to the U.S. strikes. However, he also highlighted how Iran’s ability to do that in broad daylight underscored the potential for enriched uranium and other elements of the country’s nuclear program to have been moved to other sites.
“Iran just isn’t a no-drive zone at the moment,” he wrote.
Lewis also highlighted other significant outstanding questions about the outcome of Operation Midnight Hammer, including the lack of deep-penetrating strikes on an underground facility at Isfahan and another one near the main site at Natanz. He further noted that Iran had disclosed the existence of a new enrichment facility immediately prior to the eruption of the current conflict with Israel, which the IAEA never had a chance to inspect. This is to say nothing of additional facilities that remain undisclosed to the international community that Iran could seek to make use of to continue supporting its nuclear program, including potential work on a nuclear weapon.
The New York Times had reported yesterday, citing an unnamed U.S. official, that the initial post-strike assessment of Fordow was that the site had been severely damaged, but not totally destroyed. Politico separately reported that the U.S. military had assessed earlier in the year that it could take a 30-day-long campaign of strikes, at least, to definitively neutralize nuclear sites across Iran, citing a person familiar with prior debates within the Trump administration.
In terms of the overall ongoing conflict in the region, it continues to evolve very rapidly. President Donald Trump has now downplayed the Iranian ballistic missile attack on Al Udeid Air Base in Qatar. He has also announced a ceasefire deal between Israel and Iran, which he says is set to take effect within hours, but it remains to be seen how that may unfold.
If nothing else, much still remains unknown about the current state of Iran’s nuclear program, as well as whether efforts to protect it against an Israeli raid pushed the United States to act.
Contact the author: joe@twz.com