A spokesman for the Atomic Energy Organization of Iran said Sunday that an "accident" related to the electrical system had occurred at the country's nuclear Natanz facility, which plays a central role in its nuclear development.
"Fortunately, the incident did not cause any human injuries or contamination," Behrouz Kamalvandi said, adding that the cause of the incident was under investigation."
Israeli commercial broadcaster Channel 12, citing a Western source, reported the possibility of a cyberattack on the facility, which was targeted in 2010 by the Stuxnet computer virus believed to have been jointly developed by the United States and Israel.
A mysterious explosion occurred at the same facility in July last year, damaging the building developing and assembling centrifuges used for uranium enrichment. Iran has said it was sabotage involving Israel.
Iran had just announced on Saturday that it had started up advanced IR-6 uranium enrichment centrifuges at Natanz, in a breach of its undertakings under the 2015 nuclear deal with world powers.
The agreement stipulates that Iran can only use first-generation IR-1 centrifuges for enrichment.
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