NEW YORK, New York - The head of the International Atomic Energy Agency (IAEA) says it is "deeply concerning" that Israel is carrying out attacks on nuclear facilities in Iran, warning of the dangers of radiation.

The Iran Nuclear Regulatory Authority informed the IAEA duing the first waves of attacks in the early hours of Friday morning, the Natanz Fuel Enrichment Plant site which contains the Fuel Enrichment Plant and the Pilot Fuel Enrichment Plant had the above-ground part of the Pilot Fuel Enrichment Plant, where Iran was producing uranium enriched up to 60 percent U-235, was destroyed.

Electricity infrastructure at the facility (electrical sub-station, main electric power supply building, emergency power supply and back-up generators) were destroyed, the Iranian nuclear authority told the IAEA.

At the time there was no indication of a physical attack on the underground cascade hall containing part of the Pilot Fuel Enrichment Plant and the main Fuel Enrichment Plant. However the Iranians told the UN agency, the loss of power to the cascade hall may have damaged the centrifuges there.

The level of radioactivity outside the Natanz site remained unchanged and at normal levels indicating no external radiological impact to the population or the environment from the attacks.

However, due to the impacts, there is radiological and chemical contamination inside the facilities in Natanz. The type of radiation present inside the facility, primarily alpha particles, is manageable, the Iranians told the IAEA, with appropriate radiation protection measures.

"At present, the Iranian authorities are informing us of attacks on the other facilities, the Fordow Fuel Enrichment Plant; and Esfahan site, where a fuel plate fabrication plant, a fuel manufacturing plant, a uranium conversion facility and an enriched UO2 powder plant are located. However I have to inform that at this moment we do not have enough information beyond indicating that military activity has been taking place around these facilities as well which initially had not been part of military operation," IAEA Director General Rafael Mariano Grossi said in briefing the United Nations Security Council on Friday night.

"All these developments are deeply concerning. I have repeatedly stated that nuclear facilities must never be attacked, regardless of the context or circumstances, as it could harm both people and the environment. Such attacks have serious implications for nuclear safety, security and safeguards, as well as regional and international peace and security," Grossi warned.

"In this regard, the IAEA recalls the numerous General Conference resolutions on the topic of military attacks against nuclear facilities, in particular, GC(XXIX)/RES/444 and GC(XXXIV)/RES/533, which provide, inter alia, that "any armed attack on and threat against nuclear facilities devoted to peaceful purposes constitutes a violation of the principles of the United Nations Charter, international law and the Statute of the Agency,"" the IAEA director general said. 

"Furthermore, the IAEA has consistently underlined that "armed attacks on nuclear facilities could result in radioactive releases with grave consequences within and beyond the boundaries of the State which has been attacked", as was stated in GC(XXXIV)/RES/533," Grossi added.

In addition to the targeting of nuclear facilities, the Israel Air Force, having deployed 200 warplanes in the initial phase of attacks, together with Mossad assets on the ground, assassinated nine of Iran's top nuclear scientists, as well as four of the nation's chief military commanders in Friday's attacks. 128 people in all,have been killed and more than 900 injured, with most casualties in the capital, Tehran.

In retaliatory attacks, fourteen people have been killed and hundreds injured in Israel.

Meantime in Gaza, while Israel said it had downgraded its focus to 'secondary,' 74 people trying to access aid were killed, and scores more injured on Saturday. One man said he was told the humanitarian aid centre was opening, and he decided to go to access aid, taking along his two sons. One of his sons was wounded, and the other killed. He told Al Jazeera he was not allowed to take his son's body home with him.

The Israel Air Force has had a busy 24-48 hours with pilots also hitting targets in Yemen, the Israeli Broadcasting Authority reported Saturday.

A number of Arab media sources said the target of the attacks, in the Yemeni capital Sanaa, was the top military commander of Yemen's Houthi rebels, Mohammed Abd al-Karim al-Ghamari.