Israeli jets launched air strikes across Syria on Sunday morning, encountering anti-aircraft missile fire and efforts by Syrian forces to shoot down Israeli missiles.
Syria said most of the missiles fired by Israeli jets had been shot down, while Israel said one missile exploded mid-air over southern Israel.
A Syrian army statement said missiles that flew over parts of Lebanon's capital Beirut had hit locations in the vicinity of the city of Homs, resulting only in material damage.
An Israeli military spokesman said Israeli warplanes targeted a Syrian air defence battery from which an anti-aircraft missile was launched towards Israel.
The warplanes also attacked other targets in the area, while no casualties were reported from the Syrian missile that exploded in mid-air, said the spokesman, Avichay Adraee.
Reuters could not immediately confirm whether the two incidents were related.
In the past, Israeli aircraft have approached Syrian airspace from the direction of Lebanon, using a tactic called “terrain masking” which involves using high ground as cover from enemy radar systems.
Israel has in recent months intensified strikes on Syrian airports and air bases to disrupt Iran's increasing use of aerial supply lines to deliver arms to allies in Syria and Lebanon, including Lebanon's Hezbollah
The Israeli strikes are part of an escalation of what has been a low-intensity conflict continuing for years with a goal of slowing Iran's growing entrenchment in Syria, Israeli military experts say.
Tehran's influence has grown in Syria since it began supporting President Bashar Al Assad in the civil war that started in 2011.
Fighters allied to Iran, including Hezbollah, now hold sway in areas in eastern, southern and northwestern Syria and in several suburbs around the capital.
Israeli analysts have dubbed this ongoing campaign the "war between the wars," saying it is intended to stop the creation, by Iran-backed groups, of a third missile and rocket front against Israel over the occupied Golan Heights, in addition to the existing missile threats presented by Hezbollah in Lebanon and Hamas and affiliated groups in Gaza.
Iran threat
Israel's ongoing campaign against Iran and its proxies comes amid heightened tensions between Israel and Iran as talks between the US, EU and Iran continue in order to reach a deal on Tehran's nuclear programme.
Few observers expect a return to the 2015 nuclear deal, the Joint Comprehensive Plan of Action (JCPOA) which allowed UN inspections of Iranian nuclear sites, in exchange for the lifting of a tough sanctions regime.
But recent backchannel talks between Iran and the US have shown signs on progress in some areas – the US has allowed Iraq to pay off debts worth $2.7 billion to Iran for gas imports, while Iran's Supreme Leader Ayatollah Ali Khamenei has said he is not opposed to compromise. Some say an informal bargain to de-escalate tensions could yet be reached.
On Saturday, Israeli Prime Minister Benjamin Netanyahu's national security adviser Tzachi Hanegbi said that progress in the talks might have paused plans to attack Iranian nuclear sites.
"We are not getting closer because the Iranians have stopped, for a while now, they are not enriching uranium to the level that in our view is the red line," Mr Hanegbi said.
"But it can happen. So we are preparing for the moment, if it comes, in which we will have to defend the people of Israel against a fanatical regime that is set on annihilating us and is armed with weapons of mass destruction."
On Sunday, Israel announced that it was expanding its fleet of F-35 fighter bombers, stealth aircraft that have been successfully used to evade Syrian air defences and could play a role in a potential Iran-Israel war. Iran, in turn, has said it will purchase Russian Su-35 fighter jets to bolster its ageing air fleet.
