THE death toll from a suspected chemical attack on a northern Syrian town has risen to 75, while activists and rescue workers were continuing to find terrified survivors hiding in shelters near the site.

According to a Syrian opposition group, renewed air strikes hit the town of Khan Sheikhoun a day after an attack that the Trump adminis- tration has blamed on the government of President Bashar Assad, saying that his backers, Russia and Iran, bore “great moral responsibility” for the deaths.

The UN Security Council held an emergency meeting yesterday in res- ponse to the strike, while 70 nations gathered in Brussels for a donor conference on the future of Syria and the region, pledging £4.8 billion this year.

UN Secretary-General Antonio Guterres said the suspected chemical weapons attack is a “moment of truth” that must be investigated.

Guterres told reporters at the donor conference that he hopes “this moment will be able to mobilise the capacity of all those that have resp- onsibilities in this situation”. He said: “The horrific events of yesterday demonstrate that unfortunately war crimes are going on in Syria, that international humanitarian law is still being violated frequently.”

The attack on Khan Sheikhoun left residents gasping for breath and convulsing in the streets and overcrowded hospitals. Videos from the scene showed volunteer medics using fire hoses to wash the chemicals from victims’ bodies. The attack was reminiscent of a 2013 chemical assault that was the worst in the country’s six-year conflict, leaving hundreds dead.

Syrian doctors said it is suspected that a combination of toxic gases was released during the air strikes, causing the high death toll and severe symptoms.

The Britain-based Syrian Observatory for Human Rights said 20 children and 17 women were among those killed.

Pope Francis said during his general audience that he was “watching with horror at the latest events in Syria”, and said he “strongly deplored the unacceptable massacre”.

US President Donald Trump denounced the chemical attack as an “affront to humanity”. German foreign minister Sigmar Gabriel called on Russia to endorse a planned Security Council resolution condemning the attack.

UK Foreign Secretary Boris Johnson said “all the evidence” he had seen so far “suggests this was the Assad regime ... [that] did it in the full knowledge they were using illegal weapons in a barbaric attack on their own people”.

French president Francois Hollande condemned what he called a “war crime”.

Syria’s government denied it carried out any chemical attack. Early yesterday, Russia, a major ally of the Syrian government, alleged a Syrian air strike had hit a rebel arsenal, releasing the toxic agents.

Russian defence ministry spokesman Major General Igor Konashenkov said in a statement that Russian military assets registered the strike on a weapons depot and ammunition factory on the town’s eastern outskirts. He said the factory produced chemical weapons that were used in Iraq.

The renewed air strikes hit not far from the location of the suspected chemical attack, said Ahmed al-Sheikho, of the Idlib civil defence team. He said the strikes did not cause any casualties because the area had been evacuated following Tuesday’s attack.

The Russian foreign ministry later said it opposes a draft UN reso- lution condemning the chemical attack. Ministry spokeswoman Maria Zakharova said the draft blames the Syrian government for the attack without any credible investigation.

She said that video and photo evidence of the attack presented by volunteer first responders could have been fabricated. She blamed the West for staging a “political show” and called for an international probe.

The proposed UN Security Council resolution would condemn the use of chemical weapons in Syria and stress the government’s obligation to provide information about air operations on Tuesday when the suspected chemical attack took place.

The resolution, drafted by Britain, France and the US, would also stress Syria’s requirement to give investigators the names of those in command of any helicopter squadrons on April 4. It also calls for immediate access for investigators to air bases where attacks involving chemical weapons may have been launched.

Britain’s UN ambassador said the attack in Syria’s rebel-held Idlib province “bears all the hallmarks” of Assad’s regime and that the UK believes a nerve agent capable of killing more than 100 people was used.

On Russia’s claims that a government air strike hit an opposition munitions depot, Matthew Rycroft told the emergency meeting of the UN Security Council that the UK has seen nothing that suggests any opposition groups “have the sort of chemical weapons that would be consistent with the symptoms we saw yesterday”.

“We have every indication that this was a sustained attack using aircraft over a number of hours,” Rycroft said. “We see all the signs of an attack using a nerve agent capable of killing more than a hundred people and harming hundreds more.”

He said only one air force has used such weapons in Syria and that was Assad’s.