RED WING (WCCO) — Just weeks after he went into cardiac arrest, a teenage boy returned to Red Wing High School Monday.

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Six weeks ago, a student, named Tomas, collapsed during gym class. He stopped breathing and his body was cold. He was dying, but thanks to the quick thinking of school nurse Kris Klassen and an AED, Tomas was saved.

“I’ve very happy and glad to be back,” said Lindsey Fernandez, interpreting for Tomas.

Tomas speaks mostly Spanish and he’s part of the special needs program at Red Wing — where his friends couldn’t wait to see him. His cousin, Angel, stayed with him for two straight weeks in the hospital, so he knows how much this day means to Tomas.

“He was really excited to come back, pumped for it. He wanted to come back so bad,” said Angel.

That’s because at first doctors wondered if he would ever be able to come back. Tomas was weak, but his strength has started to return to the point that doctors gave him the go-ahead. He will ease back into class, but it’s not his first time in the school since his heart stopped.

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Tomas actually came back to Red Wing High School a couple weeks ago for a fundraiser for his family. Teachers say he stopped by the AED, put his hand on it, and stood for a couple minutes without saying a word.

“I replay that day over in my head a lot of times,” said Kris.

A couple days after she helped save Tomas, Klassen took us through how it happened. The tool she never wanted to use helped her save a life. Now, she’s convinced that the heart she got beating again may be the biggest heart in the entire school.

“Tomas is alive today and, you know, the AED worked. I think everyone is celebrating that. How often do you get a happy ending like that? It’s a great feeling to have him back,” said Klassen.

Tomas thanked Klassen for helping to save his life at a fundraiser the students threw for him.

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Klassen said a lot of people played a role in saving his life and the support Tomas received on his first day back was overwhelming.