Tel Aviv: The Israel Defence Forces (IDF) said it was conducting what it called "precise" strikes against military targets in Iran.
The IDF said the strikes were in response to "months of continuous attacks from Iran." Israel had long vowed to respond to Iran's missile attack on its territory on October 1.
The Iranian assault followed the killing of the leader of Hezbollah, Hassan Nasrallah, in late September in Lebanon.
It also followed the killing of Hamas political leader Ismail Haniyeh, who was killed by an explosion in Tehran in July that Iranian officials blamed on Israel.
Israeli forces also struck some military sites in central and southern Syria on Saturday, state news agency SANA reported.
Syrian air defence forces intercepted missiles launched by Israel "from the direction of the Israeli-occupied Syrian Golan Heights and the Lebanese territories," according to SANA.
Earlier on Saturday, SANA reported explosions in the vicinity of Syria's capital Damascus.
Israel has been carrying out strikes against Iran-linked targets in Syria for years but has ramped up such raids since the October 7 attack by Hamas— which is classified as a terrorist group by many Western countries — on Israeli territory.
Biden briefed on strikes in Iran
US President Joe Biden has been briefed on the strikes in Iran, DW Correspondent Aya Ibrahim said.
The president, who is at his home in Wilmington, Delaware, is closely following the developments.
The US and its allies said for weeks that Israel had the right to defend itself but had worked behind the scenes to keep Israel from launching an attack that would spur a wider war.
Iranian airports remain operational, state media says
Iranian state TV and state news agency IRNA said that the situation at Mehrabad and Imam Khomeini airports is "normal."
"Operations at Imam Khomeini International Airport and Mehrabad Airport are normal and they continue to operate according to the schedule," the TV presenter said, citing the chiefs of Mehrabad and Imam Khomeini airports.
It also reported that Israel's strikes on Iran did not include attacks on Iranian nuclear facilities or oil fields.
US media outlets NBC News and ABC News reported so too, saying only military targets had been targeted.