A plane preparing to take off as part of the joint airstrike operation by the British, French and US militaries in Syria.
WASHINGTON - The United States, Britain and France carried out a wave of punitive strikes against Bashar al-Assad&39;s Syrian regime on Saturday in response to alleged chemical weapons attacks that President Donald Trump branded the "crimes of a monster."
As Trump embarked on a White House address to announce the action -- taken in defiance of Russia&39;s threat to respond -- explosions were heard in the Syrian capital Damascus, signalling a new chapter in a brutal seven-year-old civil war.
AFP&39;s correspondent in the city said several consecutive blasts were heard at 4am, followed by the sound of airplanes overhead. Smoke could be seen rising from the northern and eastern edges of the capital.
"A short time ago, I ordered the United States armed forces to launch precision strikes on targets associated with the chemical weapons capabilities of Syrian dictator Bashar al-Assad," Trump said, in a primetime address from the White House.
"A combined operation with the armed forces of France and the United Kingdom is now under way. We thank them both."
"This massacre was a significant escalation in a pattern of chemical weapons use by that very terrible regime," he said of the suspected deadly gas attack a week ago on the rebel-held Damascus suburb of Douma.
"The evil and the despicable attack left mother and fathers, infants and children thrashing in pain and gasping for air. These are not the actions of a man. They are crimes of a monster instead."
- &39;Heavy strike&39; -
Joseph Dunford, Washington&39;s top general, said the strikes hit three targets near Damascus -- a scientific research center, a storage facility and command post -- and a chemical weapons storage facility near Homs.
Syrian surface to air missile batteries had attempted to fire back, but there were no initial reports of allied losses, he added.
Syrian state media said air defenses were activated to block the attack as it published images of smoke clouds hanging over the capital.
"The aggression is a flagrant violation of international law, a breach of the international community&39;s will, and it is doomed to fail," the official SANA news agency said.
The strikes were a marked escalation compared to a US strike a year ago, when only cruise missiles were used against a single airfield.
Dunford said Russia&39;s forces in Syria had been warned through existing "deconfliction" channels that western planes would be in Syrian air space, but Washington had not revealed the target sites or timing in advance.
Defense Secretary Jim Mattis said no additional strikes were planned.
"We were very precise and proportionate, but at the same time, it was a heavy strike," he said.
- United front -
Trump also warned Russia and Iran not to stand by their ally in Damascus.
"Russia must decide if it will continue down this dark path or if it will join with civilized nations as a force for stability and peace," he argued.
The strikes had been expected since harrowing footage surfaced of the aftermath of the attack in Douma, which prompted a furious reaction from Trump.
Trump&39;s anger was shared by France&39;s President Emmanuel Macron, who signed his country up for a joint response.
"We cannot tolerate the normalization of the use of chemical weapons," Macron said in a statement.
Britain&39;s Prime Minister Theresa May was more cautious, but by the time the first precision cruise missile was launched, Trump had a mini-coalition.
"We cannot allow the use of chemical weapons to become normalized – within Syria, on the streets of the UK, or anywhere else in our world," May said, referring to a recent assassination attempt on a Russian double agent.