A "suspicious" blackout struck Iran's underground Natanz nuclear facility on Sunday, just hours after starting up new advanced centrifuges capable of enriching uranium more quickly. The reason for the power outage and the extent of the damage, if any, remain unclear, but Iran is calling the power outage "nuclear terrorism." Israeli media outlets, meanwhile, suggested a cyberattack occurred. The Associated Press notes these reports did not offer sourcing for the evaluation, but "Israeli media maintains a close relationship with [Israel's] military and intelligence." Israel has previously been suspected of carrying out an attack on Natanz's centrifuge assembly plant in July, and Tehran blames its rival for killing Mohsen Fakhrizadeh, the scientist who launched Iran's military nuclear program decades ago, last November. The blackout comes as world powers negotiate with Iran in Vienna over its nuclear deal.

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