Israel says its forces have struck almost all of Iran’s infrastructure in Syria, in response to an Iranian rocket attack on the occupied Golan Heights.
The Israeli military said 20 rockets were fired by Iranian Revolutionary Guards at its positions overnight.
It retaliated by targeting what it said were Iranian weapons depots, logistics sites and intelligence centres.
There was no immediate comment from Iran, which has sent troops to Syria to support President Bashar al-Assad.
Syrian state media reported that the army’s air defences had repelled an “Israeli aggression” on Syrian territory, shooting down scores of missiles.
But a military source told the official Sana news agency that some missiles had hit a number of air defence battalions, radars and an ammunition depot.
Israel’s government has vowed to stop what it considers its arch-enemy’s “military entrenchment” in Syria, and it is believed to have carried out several strikes on Iranian facilities since February.
It had been anticipating a retaliatory attack by Iran or its proxies in Syria since seven Revolutionary Guards personnel were killed in a strike on an airbase in April.
What happened in the Golan?
The Israel Defense Forces (IDF) says it has targeted dozens of Iranian facilities with air strikes in retaliation for the attack, which has not been confirmed by Iran.
It said weapons stores, missile launchers and intelligence facilities were all targeted in the wave of strikes overnight.
Syria’s state news agency Sana said Israeli missiles had been shot down south of Homs, but reported that a weapons depot and a radar installation had been hit.
Israeli Defence Minister Avigdor Lieberman warned Iran in no uncertain terms on Thursday morning.
“If it rains in Israel, it will pour in Iran,” he said.
But Mr Lieberman also added that this was not the beginning of a large confrontation.
“I hope we finished this chapter and everyone got the message,” the minister said.
The latest confrontation follows a reported Israeli missile strike on a military outpost south of the Syrian capital of Damascus on Tuesday.
Sana reported that two missiles were shot down in the Kiswah area and that two civilians were killed in an explosion.
But the Syrian Observatory for Human Rights, a UK-based monitoring group, said the missiles hit an Iranian weapons depot, killing 15 pro-government fighters.
Eight members of Iran’s powerful Revolutionary Guards force and several other non-Syrian nationals were among those killed, it said.
Israel has occupied most of the Syrian Golan Heights in the 1967 Middle East war and later annexed it in a move not recognised internationally.
Why does Israel hit Iranian interests?
Iran is Israel’s arch-foe and has repeatedly called for an end to the existence of the Jewish state.
It is a major ally of Syria and has deployed hundreds of troops to the country. It says they are there as military advisers to Syria.
Thousands of militiamen armed, trained and financed by Iran – mostly from Lebanon’s Hezbollah movement, but also Iraq, Afghanistan and Yemen – have also been fighting alongside the Syrian army.
Iran has increasingly strengthened its military presence in Syria, something which Israel considers a direct threat.
Israel has vowed to prevent Iran from entrenching itself there and has targeted, or is believed to have targeted, Iranian assets and positions, increasingly in recent months.
Prime Minister Benjamin Netanyahu has said Israel may go to war with Iran “sooner rather than later” to stop it attacking Israel.
Mr Netanyahu has been instrumental in urging Mr Trump to end his support for the nuclear agreement with Iran.
Last week, he unveiled what he said was a cache of Iranian documents proving it had not ended its efforts to build a nuclear weapon, in defiance of the deal.
Mr Netanyahu was in Moscow this week, informing Russian President Vladimir Putin, whose country is an ally of Iran and Syria, about the findings.
Israel strikes Iranian targets in Syria after rockets hit Golan Heights