Story highlights US officials say Syrian government moved planes to following US cruise missile strike

It's estimated some 20% of Syria's operational combat planes were destroyed in the attack

(CNN) The Syrian government has relocated the majority of its combat planes to protect them from potential US strikes, two US defense officials told CNN Wednesday.

The movement of the aircraft to the air base at Bassel Al-Assad International Airport began shortly after the US's April 6 Tomahawk cruise missile strike on Sharat air base, which destroyed some 24 Syrian warplanes in retaliation for a chemical weapons attack that the US says Syria launched from that airfield.

The move places the Syrian aircraft in close proximity to Russia's Khmeimim Air Base -- where the majority of Russian air forces helping ally Syrian President Bashar al-Assad's regime are based -- in Latakia Governorate, Syria.

One US defense official said that the warplanes moved appeared to be most if not all of the Syrian government's operational aircraft.

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The Khmeimim base, along with a naval facility in Tartus, is one of the two of the primary Russian military installations in Syria. The Russians have reportedly stationed advanced anti-aircraft missile systems at the base.

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