- Israeli outlets say blackout at Iran’s Natanz plant a likely Israeli cyberattack; Western intelligence sources estimate it shut down entire sections of the facility
- State TV provides few details about electrical problem; on Saturday, Rouhani inaugurated cascades of IR-6s and IR-5s at same plant, in open breach of nuclear deal
Iran’s underground Natanz nuclear facility lost power Sunday just hours after starting up new advanced centrifuges capable of enriching uranium faster, in an incident described by an Iranian lawmaker as probable “sabotage” and by unnamed Western intelligence officials as a possible cyberattack.
As Iranian officials investigated the outage, many Israeli media outlets similarly assessed that a cyberattack darkened Natanz and damaged a facility that is home to sensitive centrifuges. Some reports offered no sourcing for the evaluation, while others cited Western intelligence sources.
Public broadcaster Kan said Israel was likely behind the attack, citing Israel’s alleged responsibility for the Stuxnet attacks a decade ago. That report didn’t provide a source. Channel 12 news cited Western intelligence sources as estimating the attack shut down entire sections of the facility.
As news of the blackout emerged, US Defense Secretary Lloyd Austin landed in Israel on Sunday for talks with Prime Minister Benjamin Netanyahu and Israeli Defense Minister Benny Gantz. The US, Israel’s main security partner, is seeking to reenter the 2015 atomic accord aimed at limiting Tehran’s program so it cannot pursue a nuclear weapon. 
In this photo taken and released on April 10, 2021, by the Atomic Energy Organization of Iran, a new IR-9 centrifuge is displayed in a ceremony to commemorate Iran’s new nuclear achievements in Tehran.(Atomic Energy Organization of Iran via AP)
Power at Natanz had been cut across the facility composed of above-ground workshops and underground enrichment halls, nuclear program spokesman Behrouz Kamalvandi told Iranian state television.
“We still do not know the reason for this electricity outage and have to look into it further,” Kamalvandi said. “Fortunately, there was no casualty or damage and there is no particular contamination or problem.”
Asked by the state TV correspondent if it was a “technical defect or sabotage,” Kamalvandi declined to comment.
Malek Shariati Niasar, a Tehran-based lawmaker who serves as spokesman for the Iranian parliament’s energy committee, wrote on Twitter that the incident was “strongly suspected to be sabotage or infiltration.” He said lawmakers were pursuing details of the incident as well.
The Vienna-based International Atomic Energy Agency, which monitors Iran’s program, said it was “aware of the media reports,” but declined to comment. 
In this June 6, 2018 frame grab from the Islamic Republic Iran Broadcasting, IRIB, state-run TV, three versions of domestically-built centrifuges are shown in a live TV program from Natanz, an Iranian uranium enrichment plant, in Iran. (IRIB via AP, File)
Natanz was largely built underground to withstand enemy airstrikes. It became a flashpoint for Western fears about Iran’s nuclear program in 2002, when satellite photos showed Iran building its underground centrifuges facility at the site, some 200 kilometers (125 miles) south of the capital, Tehran.
Israel has been blamed for an attack on an advanced centrifuge development and assembly plant at Natanz in July. It has also been blamed, together with the US, for the Stuxnet virus that sabotaged Iranian enrichment centrifuges a decade ago.
Iran also blamed Israel for the killing of scientist Mohsen Fakhrizadeh last year who began the country’s military nuclear program decades earlier.
Tehran and Jerusalem are currently believed to be engaged in a maritime shadow war, with both sides blaming the other for explosions on vessels.
On Tuesday, an Iranian cargo ship said to serve as a floating base for Iran’s paramilitary Revolutionary Guard forces off the coast of Yemen was struck by an explosion, likely from a limpet mine. Iran has blamed Israel for the blast.
Israel has not claimed any of the attacks, though Netanyahu repeatedly has described Iran as the major threat faced by the country in recent weeks.
Meeting with Austin on Sunday, Gantz said Israel viewed America as an ally against all threats, including Iran.
“The Tehran of today poses a strategic threat to international security, to the entire Middle East and to the state of Israel,” Gantz said. “And we will work closely with our American allies to ensure that any new agreement with Iran will secure the vital interests of the world, of the United States, prevent a dangerous arms race in our region, and protect the state of Israel.”
Defense Minister Benny Gantz, right, walks alongside US Defense Secretary Lloyd Austin during an honor guard ceremony at Israel’s military headquarters in Tel Aviv on April 11, 2021. (Ariel Hermoni)
IDF Chief of Staff Aviv Kohavi also appeared to reference Iran in a speech on Sunday.
The Israeli military’s “operations in the Middle East are not hidden from the eyes of the enemy,” Kohavi said. “They are watching us, seeing [our] abilities and weighing their steps with caution.”
On Saturday, Iran announced it had launched a chain of 164 IR-6 centrifuges at the plant. Officials also began testing the IR-9 centrifuge, which they say will enrich uranium 50 times faster than Iran’s first-generation centrifuges, the IR-1. The nuclear deal limited Iran to using only IR-1s for enrichment.
Since then-US president Donald Trump’s withdrawal from the Iran nuclear deal in 2018, Tehran has abandoned all the limits of its uranium stockpile. It now enriches up to 20 percent purity, a technical step away from weapons-grade levels of 90%. Iran maintains its atomic program is for peaceful purposes — despite its leaders regularly threatening to destroy Israel — but fears about Tehran having the ability to make a bomb saw world powers reach the deal with the Islamic Republic in 2015.
In this photo released by the official website of the office of the Iranian Presidency, President Hassan Rouhani, second right, listens to head of the Atomic Energy Organization of Iran Ali Akbar Salehi while visiting an exhibition of Iran’s new nuclear achievements in Tehran, Iran, April 10, 2021. (Iranian Presidency Office via AP)
The deal lifted economic sanctions on Iran in exchange for it limiting its program and allowing IAEA inspectors to keep a close watch on its work.
On Friday, the International Atomic Energy Agency (IAEA) said in a report that Iran had again violated limits on its stockpile of enriched uranium, according to Reuters.
Iran met with the deal’s signatories in Vienna last week. The talks broke Friday, with no clear signs of progress.
The US said it had offered “very serious” ideas on reviving the nuclear accord but was waiting for Tehran to reciprocate.
US President Joe Biden hopes to return to the 2015 agreement, which Trump abandoned as he launched a “maximum pressure” campaign in hopes of bringing Tehran to its knees.
Iran has demanded that the United States first lift all sanctions imposed by Trump, which include a sweeping unilateral ban on its oil exports, before it falls back in line with obligations it suspended.
Talks are set to resume Wednesday with Iran again meeting the other nations in the deal — Britain, China, France, Germany and Russia as well as the European Union.
