Iran's Natanz nuclear site suffered a problem Sunday involving its electrical distribution grid just hours after starting up new advanced centrifuges that more quickly enrich uranium, state TV reported.
It was the latest incident to strike one of Tehran's most-secured sites amid negotiations over tattered atomic accord with world powers.
State TV quoted Behrouz Kamalvandi, a spokesman for Iran's civilian nuclear program, announcing the incident.
Kamalvandi said there were no injuries or pollution cause by the incident.
The word state television used in its report attributed to Kamalvandi in Farsi can be used for both "accident" and "incident." It didn't immediately clarify the report, which ran at the bottom of its screen on its live broadcast.
The Atomic Energy Organization of Iran, the civilian arm of its nuclear program, did not immediately issue a formal statement about the incident on its website.
Natanz suffered a mysterious explosion in July that authorities later described as sabotage. Israel, Iran's regional archenemy, has been suspected of carrying out an attack there, as well as launching other assaults, as world powers now negotiate with Tehran in Vienna over its nuclear deal.
On Saturday, Iran announced it had launched a chain of 164 IR-6 centrifuges at the plant, injecting them with the uranium gas and beginning their rapid spinning. 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-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% purity, a technical step away from weapons-grade levels of 90%. Iran maintains its atomic program is for peaceful purposes, but fears about Tehran having the ability to make a bomb saw world powers reach the deal with the Islamic Republic in 2015.