An explosion at the heart of Iran ‘s nuclear programme in the dead of night. An obscure group called the Cheetahs of the Homeland takes credit for it. Then there are firesand gas leaks at key infrastructure around the country. In recent days, speculation has flourished about what exactly happened at Natanz, an assembly plant for centrifuges used to enrich uranium, and other facilities around Iran. Satellite images of Natanz showa 10-metre crater and destroyed roofing material, according to the Institute for Science and International Security in Washington DC. The explosion delivered “a major setback to Iran’s abilities to deploy advanced centrifuges on a mass scale for years to come,” the institute said.

Iran’s atomic energy organisation has confirmed that the level of damage was “considerable”. The Supreme National Security Council said it knows of”the main reason” for the incident in the morning on 2 July but could not disclose it for”security purposes”. “The level of destruction strengthens the possibility of it being sabotage,” according to an article published this week in Hamshahri, a semi-official daily newspaper. The sabotage was carried out by”assailants” who moved across the desert in the dark to Natanz at 2am … because they”probably intended not to incur human losses … nor cause radioactive radiation”, Hamshahri said.

“The explosion definitely seems like an attack by the USor Israel or both like a warning that ‘we are too close to you’,” said an analyst close to reformist circles. “The act was big and caused significant [ financial] damage, making Iran’s tensions with the US even more complicated than before.”  A group called the “Cheetahs of the Homeland” has claimed responsibility.The group statement, sent by Telegram messaging app, said they were former Iranian intelligence and security agents who want to overthrow the Islamic republic. It said more attacks similar to the one at Natanz were planned.

Natanz has been targeted by cyberattacks in the past. It was hit by the computer virus Stuxnet in 2010, widely believed to have been instigated by the US and Israel. Such attacks stopped after Iran signed a nuclear agreement with world powers in 2015and halted most of its uranium enrichment activities. But after Donald Trump decided to pull the US out of the nuclear deal two years ago and began reimposing sanctions, Iran resumed various elements of its nuclear programme.

This included the assembly plant at Natanz, which since 2018 has had the capacity to build and test up to 60 advanced centrifuges at once. Satellite imagery.  s11ggr.st the. production facility h s  hr.r.n clr.strnyr.cl. Tf n r.cr.ssmy ,

security officials in Tel Aviv say that Iran could quickly bring earlier generation centrifuges online to continue enrichment, albeit at a slower speed. The blast took place about one week after an explosion at Iran’s Parchin military site which Tehran said was caused bya gas leak. There have also in recent days been fires and gas leaks in a medical clinic in the Iranian capital, a power plant in the southwestern city of Ahwaz, a petrochemical centre in the southern port cityofMahshahr and a small facto1-y in southern Tehran.