BEIRUT • Hours after the United States warned of further military action in Syria in retaliation for an apparent chemical attack on Khan Sheikhoun, the rebel-held town was hit by fresh air strikes last Friday and yesterday.
US ambassador Nikki Haley delivered the warning at an emergency session of the UN Security Council where Russia accused the US of violating international law and waging an "act of aggression" against Syria.
"The United States took a very measured step last night," Ms Haley said last Friday.
"We are prepared to do more but we hope it will not be necessary."
Damascus and its ally Moscow furiously condemned the missile strike that marked the first direct US assault on President Bashar al-Assad's government.
At the Security Council, Russia's UN envoy accused the US of violating international law by carrying out military strikes in Syria.
"The United States attacked the territory of sovereign Syria. We describe that attack as a flagrant violation of international law and an act of aggression," said deputy ambassador Vladimir Safronkov.
US Secretary of State Rex Tillerson, who is scheduled to go to Moscow on Tuesday, said he was disappointed but not surprised by the Russian reaction because it showed continued support for Mr Assad.
Ms Haley said the US strikes destroyed the Shayrat airfield from which the US believes the attacks on Khan Sheikhoun last Tuesday were launched, killing 86 people, including 27 children.
CNN reported that the town in the north-western province of Idlib province came under attack again last Friday and yesterday, leaving at least one woman dead and three people injured yesterday. It was not immediately clear who conducted the aerial assaults.
Meanwhile, an air strike yesterday, believed to have been carried out by the US-led coalition against the Islamic State in Iraq and Syria, killed 15 people, including four children, in the Hanida village, west of the militants' stronghold of Raqqa, the Syrian Observatory for Human Rights said.
The US strike against Syria has threatened Russian-US relations as the Kremlin denounced US President Donald Trump's use of force.
As many as 100 Russian troops were believed to have been stationed at the Shayrat airbase when it was targeted by the US.
Moscow said it would bolster Syria's air defences and the Russian news agency Tass reported that a frigate was due to enter the Mediterranean Sea last Friday - an apparent bid by Russia to flex its military muscles - and visit the logistics base at Tartus, a Syrian port.
North Korea said yesterday the US missile strikes were "an unforgivable act of aggression" that showed its decision to develop nuclear weapons was "the right choice a million times over".
Pyongyang is believed to be developing missiles capable of hitting the US and a nuclear arsenal in defiance of UN sanctions.
The swift developments in Syria prompted Britain's Foreign Secretary Boris Johnson yesterday to cancel a scheduled visit to Moscow this week.
REUTERS, AGENCE FRANCE-PRESSE, NYTIMES