The U.S. missile strike targeting a major Syrian air base near Homs early Friday destroyed about 20 Syrian jets, two senior defense officials with knowledge of the strike told Fox News.

WH photo (ed for security): @potus receives briefing on #syria military strike fr Nat Security team, inc @vp , SECDEF, CJCS via secure VTC pic.twitter.com/aaCnR7xomR — Sean Spicer (@PressSec) April 7, 2017

None of the jets managed to take off and escape before U.S. missiles hit the target, the officials said, adding that all of the destroyed aircraft were jets -- not helicopters. No Russian aircraft were at the Sharyat airfield.

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The U.S. launched 60 missiles in all. It was believed that one missile failed and likely fell into the sea, but defense officials were still assessing where it landed.

Two U.S. destroyers, the USS Ross and USS Porter, launched the Tomahawk cruise missiles south of Cyprus in the Eastern Mediterranean Sea.

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Fox News is told the missiles were the Tomahawk “E” or Echo version. It is the latest model and has two-way satellite communication allowing the missile to be reprogrammed in flight if needed. The missiles can carry 1,000-pound warheads.

Fox News is told the mission is complete. There have been no additional orders to shoot more missiles, but there are still some remaining missiles on board each of the two U.S. destroyers.

Each destroyer carries about 35 Tomahawks.

The Russians were warned about an hour before the missiles hit the base, the defense officials said.

U.S. Central Command, headquartered in Florida, planned this mission. Army Gen. Joe Votel leads the organization in charge of all American forces and operations in the Middle East.

Fox News' Jennifer Griffin and Lucas Tomlinson contributed to this report.