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From bombing a home of President Bashar Al Assad's brother to striking a military headquarters in Damascus, Israeli raids on Syria have intensified in pursuit of key supply lines to Hezbollah, a development that could damage the alliance between the Iran-backed militant group and the Syrian leader.
Since the outbreak of the Syrian civil war in 2011, Iran has carved out a zone of control in the country, turning it into a logistics, weapons development and manufacturing lifeline for Hezbollah, security experts say. Syria has also become a launch pad for drug smuggling by cartels linked to the armed group.
Israel has responded with thousands of air raids on weapons sites and supply lines in Syria over the past decade, along with drone and roadside bomb attacks. The strikes have killed hundreds of commanders from Hezbollah as well as Iran's Islamic Revolutionary Guard Corps and members of the Syrian military. Israel also bombed a suspected nuclear research site in eastern Syria in 2007.
But two incidents in the past month indicate Israel has upped the ante, keen to prevent Hezbollah from retreating from Lebanon into its backlines in Syria. Israel is seeking to weaken Iran's ability to activate another front in the fighting based in Syria, from where it could inflict damage on Israeli troops in the Golan Heights, according to members of Syria's political opposition who specialise in reconnaissance.
On September 8, Israeli special forces reportedly mounted a rare ground raid in the central Syrian area of Masyaf, about 240km north of the Israeli border, storming a weapons development site overseen by Iran.
A senior Syrian opposition member said “it was a game-changer”, because the site is linked to Iranian hardware that Tehran has been supplying to Russia for use in the Ukraine war. The raid indicated Israel is not afraid of further friction with Russia in its pursuit of Iran and Hezbollah, he said.
About four weeks later, Israeli planes raided a villa in the upmarket Damascus suburb of Yafour, considered a fief of Maher Al Assad. The sibling is the second most powerful man in Syria’s ruling system, which is dominated by the Alawite sect.
Maher leads the elite Fourth Mechanised Division, which controls border areas of Syria still under the authority of the government.
Although there were no reported casualties, the attack "showed that there are no longer red lines" in Israeli operations in Syria, while Maher "has been placed on the Israeli targets list", another Syrian source said.
"Maher is the main regime link for Iran in Syria, especially for the weapon supplies through the border with Iraq, or the drug smuggling through Jordan."
Mr Maher rarely appears in public. Although he is only a major general, he is widely seen as the de facto head of the Syrian military and the muscle behind his brother's rule. In 1999, he shot his late brother-in-law, Assef Shawkat, during an argument, reinforcing his tough-guy image. Mr Shawkat, who was later killed in a mysterious 2011 explosion in Damascus, was flown to France for treatment after the shooting and survived.
Since the Yafour attack, Israel has struck a weapons depot in the countryside of the central Syrian governorate of Hama, as well as other depots. It has also hit an industrial area linked to Iran near Homs, according to Syrian regime loyalists, who have released footage on social media purporting to show the strikes.
There have been increasing sightings of Israeli surveillance drones, particularly on the coast and near the border with Lebanon. One drone strike on Damascus last week reportedly killed Hassan Jaafar Al Qasir, a relative of late Hezbollah leader Hassan Nasrallah, himself assassinated by Israel two weeks ago. Mr Al Qasir was in charge of the group's financing and stealth accounts, according to Israeli and Arab media.
The Syrian opposition source said that, despite Israel's recent military successes, it is still dangerously exposed to a network of militias that Iran and Hezbollah have built opposite Israeli positions in the Golan Heights, across a 1974 armistice line separating Israel and Syria.
"I would not be surprised if Israel's next incursion will be across the Golan, to neutralise the Hezbollah proxies and bases there," he said, adding that such an operation would also be designed to prevent Iran from moving thousands of Iraqi Shiite militias to the Golan from Damascus and eastern Syria.
The rising tension could put Mr Assad, who owes his survival to Iran, in a quandary, the source said. “If Tehran asks him to take part in an offensive in the Golan and he does, Israel will dispose of him. If he refuses, Tehran will.”
Israel is considering a response to an Iranian missile attack last week that was launched in retaliation for Nasrallah's assassination. The barrage caused no significant casualties but Israel said it will not go unanswered.
Waiel Olwan, senior researcher at the Jusoor Centre for Studies in Istanbul, said Hezbollah and Iran are suspicious that Syrian spies may have helped Israel in its recent penetration of Hezbollah's command structure, but Hezbollah's leadership could still move some of its meetings to Syria in the wake of Israeli air strikes on its strongholds in Beirut.
Veteran Syrian political commentator Aymen Abdel Nour said that although no Arab country has endorsed the Israeli operations, US allies in the region are united that Hezbollah and the other major militias in the area must be neutralised.
“They are being pursued everywhere, whether they are the PKK [Kurdistan Workers' Party], Hamas, Hezbollah, the Houthis and even the Muslim Brotherhood," he said.
Mr Abdel Nour said the Israeli strikes in Syria are "pre-emptive" to prevent Hezbollah from launching a new front against Israel. "They are hitting radar facilities, precision weaponry manufacturing sites, drone manufacturing, tunnels and other supply lines, from Syria to Lebanon, Iraq to Syria."
The Syrian President, as part of a strategic alliance with Iran, could be pursued under apparent new Israeli rules that "those complicit with Hezbollah" must be tackled.
Mr Abdel Nour predicted the current Israeli onslaught would limit Iran's sway in Syria, while Tehran will need to rely more on Russia to protect its presence in the country. He highlighted a recent air cargo of Iranian aid to pro-Hezbollah Lebanese refugees in Syria, which he said was inspected by Russian troops at Latakia airport.
"The era of non-state actors" holding great influence in the Middle East, he said, appears to be on the wane.
