Oman and Qatar were leading efforts to begin ceasefire talks, while mediators said Iran was open to resuming nuclear negotiations if Israel’s attacks stop.

Dozens of others were injured overnight across Israel, the authorities said. Israel was striking military sites in Iran and the four-day-old conflict showed no sign of slowing.

Iran has arrested dozens of people on suspicion of spying as fears grow in the Islamic Republic over the extent of its infiltration by Israel’s Mossad intelligence service.

Blasts rang out across a swath of the Middle Eastern republic’s territory, targeting its nuclear capabilities, military leadership and scientists.

U.S. refueling aircraft and warships have been dispatched to safeguard U.S. interests as the deadly conflict shows no sign of abating.

The head of the International Atomic Energy Agency says there is a possibility of both radiological and chemical contamination within Iran’s main nuclear enrichment facility in Natanz.

Since Israel began its concerted attack on Iran on Friday, calls for regime change in Iran have grown louder – from hawks in the US Congress to Israeli officials and some Iranian activists abroad.

Israel's airstrikes have deepened a climate of fear within Iran, where there is a shortage of reliable information. A woman in Tehran said one of the worst things about the attacks is that they usually come without warning.