At least three USA ships, as well as piloted warplanes, participated in the airstrikes.
The Pentagon said one of the targets was a scientific research center located in the greater Damascus area, which it described as a Syrian center for the research, development, production and testing of chemical and biological weaponry.
"A perfectly executed strike last night".
Later state TV broadcasts also show the fragments of an apparent British missile as well as debris from the attack.
"We will try to make it better but it is a troubled place", Trump said.
May said the missile strike, created to minimize civilian casualties, was aimed at deterring further use of chemical weapons and was not an attempt to topple the Syrian government. We can not allow the use of chemical weapons to become normalised - within Syria, on the streets of the United Kingdom, or anywhere else in our world. "Clearly the Assad regime did not get the message a year ago", Mattis said. "The opposition does not operate helicopters or use barrel bombs".
In April 2017, the USA struck an airbase in Syria using cruise missiles.
RAF Tornado jets set off in the early hours, with The Ministry of Defence deeming the mission a "success", according to reports.
The Organisation for the Prohibition of Chemical Weapons (OPCW) has dispatched a fact-finding mission to the site of the alleged attack in Syria. It was done on targets that we believed were selected to hurt the chemical weapons program.
What are others saying about the attack?
Russian Federation and Iran, supporters of the Assad regime, condemned the strikes.
"Kremlin's support of Damascus's crimes can not be left without attention, as the Kremlin's regime with its actions, including in the UN Security Council, consistently makes it impossible to solve the conflict in Syria in accordance with the UN Charter", the statement says.
The Prime Minister said she will go before the Commons on Monday to answer questions about her decision but insisted there was no "alternative path".
Trump said he also has a message for the two governments most responsible for supporting, equipping, and financing the criminal Assad regime.
Western powers blamed President Bashar al-Assad, but Syria and its ally Russian Federation categorically denied the claims and accused the West of "fabricating" the incident to justify military action. Russia's US embassy released a statement warning that the airstrikes will "not be left without consequences".
They "are responsible for the regional consequences of this adventurist action", it said, condemning a "clear violation of worldwide rules and laws".
At an emergency U.N. Security Council meeting Saturday, the USA envoy said the U.S.is "locked and loaded" if the Syrian regime is "foolish enough to test our will".
Loud explosions rocked Syria's capital and filled the sky with heavy smoke early Saturday after USA president Donald Trump announced airstrikes in retaliation for the country's alleged use of chemical weapons.