American military saw Syrian fixed-wing aircraft drop chemical weapons on civilians in Idlib this week, two officials told NBC News.

Americans saw the aircraft on radar and watched bombs fall, the officials said. The attack killed dozens of people, including 25 children, and injured at least 350 others.

The bombs hit a hospital run by the al Qaeda-linked al-Nusra Front, damaging operating rooms and injuring medical professionals, the officials said.

Turkey said Thursday that autopsies conducted on victims of the attack showed chemical weapons were used. Syria has maintained that it did not use chemical weapons.

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