Russia has expressed concern at an alleged Israeli attack on Syria, saying such a strike would be an unacceptable violation of the United Nations Charter.
Syria's army said Israeli jets had targeted a military research centre north-west of Damascus on Wednesday. It denied reports that trucks carrying weapons bound for Lebanon were hit.
Russia has steadfastly refused to denounce Syrian President Bashar al-Assad during the 22-month conflict that has killed more than 60,000 people, the BBC reports.
The Syrian army statement, carried on state media, said Israeli fighter jets had carried out a direct strike on a scientific research centre in Jamraya, killing two people and injuring five.
The Russian Foreign Ministry said: "If this information is confirmed, then we are dealing with unprovoked attacks on targets on the territory of a sovereign country, which blatantly violates the UN Charter and is unacceptable, no matter the motives to justify it."
Relations between Russia and Israel have been improving in recent years as trade and economic ties have grown stronger. But Moscow is a close ally of President Assad, which would explains its concern, the BBC reports.
The attack came as Israel voiced fears that Syrian missiles and chemical weapons could fall into the hands of militants such as the Lebanese Shia militant group Hezbollah.
Israel and the United States have declined to comment on the reported incident.