Syria’s army said Israel targeted one of its positions in Hama province early on Thursday, which a war monitor said was a branch of the government agency accused by the US of producing chemical weapons.
An army statement said the airstrike killed two people and caused material damage near the town of Masyaf and warned against the “dangerous repercussions of this aggressive action to the security and stability of the region”.
The war monitor, the Syrian Observatory for Human Rights, said the strike hit a Scientific Studies and Research Centre facility, the agency the US describes as Syria’s chemical weapons manufacturer.
The strike took place on the tenth anniversary of Israel’s destruction of Syria’s nuclear reactor and the morning after UN investigators said the Syrian government was responsible for a sarin poison gas attack in April.
Syria’s government denies using chemical weapons and in 2013 it promised to surrender its chemical weapons programme, which it says it has done.
The Observatory said strikes also hit a military storage camp next to the centre that was used to store ground-to-ground rockets and where personnel of Iran and its allied Lebanese Hezbollah group had been seen more than once.
An Israeli army spokeswoman declined to discuss reports of a strike in Syria, saying the army does not comment on operational matters.
However, Israeli officials have in the past admitted that Israel has repeatedly struck weapons shipments bound for Lebanon’s Iran-backed Hezbollah group, an ally of Syrian President Bashar al-Assad, without specifying which ones.
In an interview in Haaretz last month upon his retirement, former Israeli air force chief Amir Eshel said Israel had struck Syrian and Hezbollah arms convoys nearly 100 times in the past five years.
Israel sees a red line in the shipment to Hezbollah of anti-aircraft missiles, precision ground-ground missiles and non-conventional (chemical) weapons.
Hezbollah and Israel fought a brief war in 2006 and both have suggested that any new conflict between them could be on a larger scale than that one, which led to the deaths of more than 1,300 people.
In May, an official in the military alliance backing Assad said that Hezbollah drew a distinction between Israel striking its positions in Syria and at home in Lebanon. “If Israel strikes Hezbollah in Lebanon, definitely it will respond,” the official said.
The Syrian army statement said the Israeli strike, which it said took place at 2.42am (23.42GMT), had been made in support of Islamic State.
Amos Yadlin, a former head of Israeli military intelligence, tweeted that the reported attack was not routine and targeted a Syrian military scientific centre.
“The facility at Masyaf also produces chemical weapons and explosive barrels that have killed thousands of Syrian civilians,” Yadlin said in the tweet.
The UN Commission of Inquiry on Syria said on Wednesday that a government jet dropped sarin on Khan Sheikhoun in Idlib province in April, killing more than 80 civilians, and that government forces were behind at least 27 chemical attacks.
Israeli officials have also previously said that Russia, another Assad ally, and Israel maintain regular contacts to coordinate military action in Syria.
Jets flying over Lebanon overnight broke the sound barrier and Lebanese media reported that some Israeli jets had breached Lebanese airspace.
