"Moscow is deeply concerned about the reports of an attack by Israel's Air Force on Syrian facilities near Damascus.
If this information proves true, then we deal with unsanctioned strikes on targets in the territory of a sovereign state, which is a blatant violation of the UN Charter and is unacceptable no matter what reasons are behind the attack," the Russian Foreign Ministry said in a statement posted on the ministry's official website on Thursday.
"We are taking urgent measures to clarify the situation in detail," the statement reads.
The Russian Foreign Ministry has again called to end "any violence in Syria, to prevent any external interference and to launch a pan-Syrian dialog on the basis of Geneva agreements dated June 30, 2012," it reads.
Voice of Russia, Interfax
The United Nations Organization has no evidence of Israeli air strike against Syria, spokesman Eduardo Del Buey said.
He, however, admitted that UN peacekeepers headquartered in southern Lebanon noticed that Israeli air forces were on a heightened regime of alert.
On Wednesday Syria`s official media said that Israeli jets had carried out a direct strike on a scientific research centre outside Damascus, killing 2 people and injuring 5 more.
Voice of Russia, TASS
Israeli warplanes attacked a military research center in Damascus province at dawn on Wednesday, Syria's military command said, denying reports that the planes had struck a convoy carrying weapons from Syria to Lebanon.
According to the agency, at dawn on January 30, Israeli warplanes violated Syrian airspace, with the jets bombing an army research center in the area of Jamraya, northwest of the capital which it described as one of a number of "scientific research centers aimed at raising the level of resistance and self-defense".
Two people were killed and five wounded.
"Israeli military aircraft violated our airspace at dawn and carried out precision attacks targeting the scientific research facility," – the agency quotes a statement of the supreme command of the Syrian armed forces.
The building was destroyed, the military command said in a statement carried by state media. Earlier, the center was targeted by armed opposition groups.
It said the planes crossed into Syria below the radar level, just north of Mount Hermon, and returned the same way.
Sources told Reuters earlier that Israeli jets had bombed a convoy on Syria's border with Lebanon on Wednesday, apparently targeting weapons destined for Hezbollah.
The air attack carried out by Israel on a Syrian target has been confirmed by the United States. According to Washington, the strike did not target the research institute, but a convoy of trucks, allegedly carrying weapons.
Tel Aviv fears that Damascus may hand over chemical weapons or sophisticated anti-aircraft missiles to the Islamist movement Hezbollah.
On the same day it became known that citizens of the Jewish state were stocking up on gas masks. The demand for them tripled at the end of January. Many Israelis believe that their country could face an assault with Syrian chemical weapons, RBC reports.
Voice of Russia, Reuters, RBC