Doctors and rescue workers in Syria said at least 42 people were killed in an apparent chemical attack on a rebel-held town of Douma, in eastern Ghouta, located near the capital of Damascus. Rescue workers said they found families suffocated in their homes and shelters and videos spread online showing purported victims of the attack. “The attack was near bomb shelters and so it spread quickly in them,” a paramedic who helped treat a group of victims said. “The gas was concentrated and in a place where people thought they were safe.

The opposition-linked Syrian Civil Defense, known as the White Helmets, made clear the death toll is likely to rise as rescue operations continue. A joint statement with the Syrian Medical Society, a relief organization, said more than 500 people, mostly women and children, were taken to medical centers with “signs of respiratory distress, central cyanosis, excessive oral foaming, corneal burns, and the emission of chlorine-like odor.” After the chemical attack, the targeted area and the hospital that was treating the injured “were attacked with barrel bombs, which hindered the ability of ambulances to reach the victims.” The White Helmets posted several devastating videos and photos showing victims of the attack, including toddlers in diapers with foam coming out of their mouths.

Another Video showing cases of suffocation among civilians, mostly children and women, following the chemical attack against the civilians in #Douma city. #AssadHitsDoumaWithChemicals pic.twitter.com/ItEpVLq5zM — The White Helmets (@SyriaCivilDef) April 8, 2018

The Syrian and Russian government both denied the use of chemical weapons, blaming rebels for trying to create an international outcry as the government is moving quickly to retake control of the suburb, which is one of the last rebel strongholds close to the capital. but that didn’t stop foreign governments from expressing outrage at the reports. The British Foreign Office called for an investigation, noting that it would be “further proof of Assad’s brutality.” President Donald Trump, meanwhile, took to Twitter to affirm that it was indeed a “mindless CHEMICAL attack” and blamed “President Putin, Russia and Iran … for backing Animal Assad.” He called on Syria to “open area immediately for medical help and verification” before pointing the finger at his predecessor: “If President Obama had crossed his stated Red Line In The Sand, the Syrian disaster would have ended long ago!”

Many dead, including women and children, in mindless CHEMICAL attack in Syria. Area of atrocity is in lockdown and encircled by Syrian Army, making it completely inaccessible to outside world. President Putin, Russia and Iran are responsible for backing Animal Assad. Big price... — Donald J. Trump (@realDonaldTrump) April 8, 2018

....to pay. Open area immediately for medical help and verification. Another humanitarian disaster for no reason whatsoever. SICK! — Donald J. Trump (@realDonaldTrump) April 8, 2018

If President Obama had crossed his stated Red Line In The Sand, the Syrian disaster would have ended long ago! Animal Assad would have been history! — Donald J. Trump (@realDonaldTrump) April 8, 2018

This latest reported attack comes at a complicated time for Trump, who had ordered a strike after a chemical attack last year but has said recently he wants the United States out of Syria. For now, the administration is keeping its options open. “I wouldn’t take anything off the table,” White House Homeland Security and counterterrorism adviser Thomas Bossert said on ABC’s This Week.

With concerns over another chemical attack in Syria, @TomBossert45 tells @MarthaRaddatz: “This is one of those issues on which every nation, all peoples, have all agreed, and have agreed since WWII, is an unacceptable practice… I wouldn’t take [military action] off the table.” pic.twitter.com/c7I9NidTy6 — This Week (@ThisWeekABC) April 8, 2018

In a statement, the Syrian government said the claims of the use of chemical weapons were nothing short of “fabrications” from rebels who are losing to government forces. “The army, which is advancing rapidly and with determination, does not need to use any kind of chemical agents,” the statement said. For its part, the Foreign Ministry in Moscow, warned that any military strike as a response to “fabricated” reports of chemical attacks would lead to the “gravest consequences.”