The Russian Defense Ministry said Syria shot down a "significant number" of the missiles, and made it clear that Russia's missile defense systems were not involved in intercepting the missiles.
“More than 100 cruise missiles and air-to-land missiles were fired by the US, Britain and France from the sea and air at Syrian military and civilian targets,” the ministry said in a statement quoted by RIA Novosti news agency.
Reuters quoted an unnamed Syrian official as saying that a third of the missiles fired in the aggression were shot down. The source also said the targeted sites had earlier been evacuated upon Russia’s warning.
“We have absorbed the strike,” he said. “We had an early warning of the strike from the Russians ... and all military bases were evacuated a few days ago.”
"Around 110 missiles" were fired at Syrian targets in Damascus and its outskirts, the Syrian Army spokesperson in an official announcement on Syrian state TV.
Lebanon's Hezbollah movement praised the Syrian air defense for confronting "tripartite aggression".
Shortly after the attack, a group of Syrian people gathered at Umayyad Square in central Damascus to protest the air raids on their homeland. The protesters carried Russian, Iranian, Syrian and Hezbollah flags.
The Syrian presidency posted a video that appeared to show President Bashar al- Assad arriving for work after the attack.
Syria's Foreign Ministry denounced the strikes as a "brutal, barbaric aggression" aimed to block a probe by the Organization for the Prohibition of Chemical Weapons, a global watchdog.
"The timing of the aggression coincides with the arrival of OPCW mission to Syria to investigate the alleged chemical attack in Douma, and mainly aims at hindering the mission's work and preempting its results," it said in comments carried by state news agency SANA.
The ministry said it was an "attempt to block the exposure of their lies and fabrications".
The attack, it said, will not have any impact on the Syrian army's resolve to press the fight against militants and restore control of the entire country.
"The barbaric aggression ... will not affect in any way the determination and insistence of the Syrian people and their heroic armed forces," SANA cited an official source in the ministry as saying.
"This aggression will only lead to inflaming tensions in the world" and threatens international security, it added.
The agency had earlier slammed the attack as "a flagrant violation of international law, a breach of the international community's will, and it is doomed to fail."
SANA reported that the joint operation was targeting military installations around Damascus and near the central city of Homs.
It said three civilians were wounded in the Homs attacks but did not give a toll for Damascus or mention any combatant casualties.