Natanz (TIP): Iran‘s underground Natanz nuclear facility lost power on Sunday just hours after starting up new advanced centrifuges capable of enriching uranium faster, the latest incident to strike the site amid negotiations over the tattered atomic accord with world powers.

As Iranian officials investigated the outage, many Israeli media outlets offered the similar assessment that a cyberattack darkened Natanz and damaged a facility that is home to sensitive centrifuges. While the reports offered no sourcing for the evaluation, Israeli media maintains a close relationship with the country’s military and intelligence agencies.

If Israel caused the blackout, it further heightens the tensions between the two nations already engaged in a shadow conflict across the wider West Asia.

It also complicates efforts by the US, Israel’s main security partner, to re-enter the atomic accord aimed at limiting Tehran’s programme so it couldn’t pursue a nuclear weapon if it chose.

Power at Natanz had been cut across the facility comprised of above-ground workshops and underground enrichment halls, civilian 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 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 “very suspicious,” raising concerns about possible “sabotage and 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. Iran also blamed Israel for the killing of a scientist who began the country’s military nuclear program decades earlier. AP