EXCLUSIVELY ON "60 MINUTES": RARE VIDEO OF A 2017 SARIN GAS ATTACK ON SYRIAN CIVILIANS SHOWS THE HORRORS OF THE WAR THAT CONTINUES TO RAGE IN SYRIA

100 Killed, 200 Injured - Mostly Women and Children -- in the Syrian Town of Khan Shaykhun

"Like the Apocalypse," Says Doctor Treating Victims

60 MINUTES has obtained rare video of the Syrian gas attack on civilians that drew a 59-missile response by the U.S. military last year. The disturbing high-definition video, shown publicly for the first time, exposes the horrible effects of these internationally banned weapons that the Syrian dictator Bashar al-Assad continues to use to massacre his people. There have been six known gas attacks by the Syrian government since the New Year and approximately 200 since 2011. Scott Pelley's story about this sarin nerve gas attack that killed an estimated 100 people and injured 200 in a Syrian town will be broadcast on 60 MINUTES Sunday, Feb. 25 (7:00-8:00 PM, ET/PT) on the CBS Television Network.

The farming village of Khan Shaykhun in rebel-held territory was bombed with sarin gas on April 4, 2017, says Edmond Mulet, who led an investigation by the United Nations and the Organisation for the Prohibition of Chemical Weapons into the attack. "We have the big crater, sarin was released... around a hundred were killed," he tells Pelley. "More than 200 were affected, mainly children and women."

Syrian Civil Defense first responders, better known as the "White Helmets," came to the aid of the victims and took much of the graphic video seen in Pelley's report. "People were fainting, completely unconscious... trembling and convulsions, foam coming out of the... mouth. Some people were already dead," recalls Mustafa al-Haj Yousef, the White Helmets supervisor.

Pelley spoke to a doctor who treated the victims. Dr. Mamoun Morad inhaled traces of the gas as well. His throat was still raspy months after the attack. Those closest to the bombing, especially children, suffered the most. "We washed the boy... washed... washed... washed... but he didn't make it... .There are no words. It was like Judgment Day, the Apocalypse."

Pelley spoke to Mulet a few hours before he lost his job; Syrian ally Russia used its veto power on the U.N. Security Council to end Mulet's investigation into Syrian chemical weapons. "The investigations we have conducted have proven that the sarin that has been used in Syria has come from an original stockpile... distilled by the Syrian government some years ago," he says.

The Syrians claim the rebels staged the attack to make the government look bad. But Mulet says it would have been too difficult for them. "You need very sophisticated and big laboratories to [make sarin]... one single drop here right now would be killing everybody in this studio."

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