Beirut - Israeli aircraft struck "centres for scientific research" north-west of Damascus near the Lebanese border, killing two people and wounding five, the Syrian Army said.
"Israeli warplanes infiltrated our airspace this morning and scored direct hits on centres for scientific research responsible for enhancing the resistance and self-defence in Jarmaya on the outskirts of Damascus," the military said on Wednesday in a statement carried by state-run media.
Syria said the casualties were employees at the facility.
State television said the Israeli jets entered Syrian airspace via Mount Hermon, which straddles the border between Syria, Israel and Lebanon, and managed to avoid radar detection.
"The strike caused heavy material damage and destroyed the building," state television quoted the military as saying.
It said at least six rockets hit the complex and set the building ablaze.
Convoy attack claim denied
"This assault is one of a long list of acts of aggression against the Arabs and Muslims," the army statement said.
The army denied earlier reports that Israeli forces had launched an airstrike overnight on a convoy believed to be carrying weapons from Syria near the border with Lebanon.
The announcement came hours after media reports said Israeli jets had struck a convoy trying to enter Lebanon from Syria.
The Syrian Army statement said the airstrike occurred after rebel fighters for months had tried and failed to overrun the sites in Jarmaya, 14km from the Lebanese border.
Israel and Western countries have expressed concerns that Syria's large stockpile of chemical weapons could fall into the hands of the pro-Iranian Lebanese Hezbollah or groups affiliated with the terrorist network al-Qaeda.
Israeli officials notified the United States of the raid, The New York Times reported late on Wednesday, citing US officials speaking on the condition of anonymity. The US officials said they believed the airstrike was aimed at a convoy of anti-aircraft weapons bound for Hezbollah, the Times said.
Israel fears that sophisticated anti-tank and anti-aircraft weapons supplied to Syria by Russia could end up with Hezbollah, a Damascus ally.
On Sunday, Israel moved two Iron Dome anti-missile defence batteries to the north.
The Lebanese Army said four Israeli planes had mounted overnight overflights in southern Lebanon.
The Israeli military declined to comment on the reported strike.
Anderea Tenti, spokesperson for UN forces in Lebanon, said, "We have no information yet, but we are looking into it."
Israel has recently expressed fears about the fate of non-conventional weapons in Syria.