The Britain-based Syrian Observatory for Human Rights said at least 58 people died, including 11 children, in the early morning attack in the town of Khan Sheikhoun.
Mostafa Kattaa grew up in Syria.

"I cannot believe I'm living in the 21st century," Kattaa said.

Kattaa moved from Syria at 25 years old to pursue his education.

"I know different parts of Syria," Katta said. "It's happy. The people are very simple. It's very hard because I have childhood memories."

Kattaa said he has many relatives who live throughout Syria and the news of what happened was hard to hear.

"This is really painful," Kattaa said. "I heard the news in the morning. It ruined my whole day."

Videos show victims suffering and volunteers using hoses to wash off chemicals from their bodies. What's most hard for many parents like Reem Alolaby to watch are the children.

"Me being a mom I know now more than ever losing a child is one of the hardest anyone can pass with," Alolaby said.