Mason Schermerhorn last texted his mom from the restroom before he was discovered as one of the four killed in a mass shooting at Apalachee High School in Winder, Georgia, a chaplain and youth minister who tried to help find the teen said. 

Ronald Clark had stopped at a store on his way home Wednesday morning, when he learned of the shooting from his wife via phone call.

He rushed to the scene, and quickly offered his services to law enforcement at the command post. He was instructed to assist crews on the investigative side. 

About an hour later, he said he started seeing the students, who were "hurt."

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"You want to have the arms big enough to grab everybody, but it's only so much that you can do," he said, calling the situation "challenging."

He described the look on victims' faces as "shock," and said those who provided their testimonies to him in an attempt to cope were "strong."

About 30 minutes later, Clark said he began assisting Schermerhorn's mother, who is his coworker, with trying to find him.

"It was hard, because we were just talking about her kids on Tuesday this week," Clark said. "She was saying that the bond and the connection she has with her kids is unbreakable."

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Schermerhorn's mother told the chaplain she believed that the 14-year-old autistic student was okay.

"'Hey, I can't find him," Clark remembers her saying. "'I'm just here to pick him up. I know he's safe. He text me that he's in the restroom. Can you please help?'"

Clark then took a photo of the teen to the command post, where he quickly learned that Schermerhorn was one of the "confirmed" dead. 

"He was a great kid, from what I was told. Loved life, didn't have any issues with anyone. He was autistic, but that didn't stop his glow," Clark said.  

As for any advice the youth minister could give parents, it is to maintain communication with their kids. 

"You don't understand how much we are valued at home," he said, adding that some children's faces lit up on Wednesday when they were reunited with their parents following the school shooting. "Pay attention to your children."