TEHRAN, June 19 (Xinhua) -- Iran's atomic chief on Thursday called on the United Nations nuclear watchdog to immediately end its "inaction" and condemn Israeli attacks on Iran's "peaceful" nuclear facilities, according to the semi-official Fars News Agency.

Head of the Atomic Energy Organization of Iran Mohammad Eslami made the remarks in a letter addressed to President of the International Atomic Energy Agency (IAEA) Rafael Grossi following an Israeli strike on the Arak heavy water research reactor facility in Khondab County in Markazi province early Thursday.

Eslami called on the IAEA to immediately end its "inaction" and condemn Israel's actions, which are in contradiction with international law.

The conflict between Israel and Iran entered its seventh day on Thursday. It started after Israel on June 13 launched airstrikes on Iran, hitting the country's military and nuclear sites and killing several top military commanders and nuclear scientists.

Iran responded by also launching missile and drone attacks against targets in Israel.

Earlier on Thursday, a missile struck a building at Soroka Medical Center in southern Israel, injuring at least 71, according to Israel's Health Ministry.

Iran's mission to the UN refuted the claim, saying the strike was aimed at the Israeli army's C4I telecommunications corps headquarters and an intelligence facility.

The mission said Iran was committed to international humanitarian law and did not target civilians and non-military infrastructure.