Shawn Mendes and Khalid paid an emotional tribute to those affected by gun violence at the Billboard Music Awards Sunday night, earning them a standing ovation.

The duo performed their duet "Youth" live for the first time. Twelve members of the Marjory Stoneman Douglas High School student choir joined them on stage. The students, wearing matching black "Youth" sweaters, joined Mendes and Khalid on stage for the chorus.

Khalid wore a t-shirt with the words "Protect our children."

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LAS VEGAS, NV - MAY 20: Recording artist Shawn Mendes (C) onstage during the 2018 Billboard Music Awards at MGM Grand Garden Arena on May 20, 2018 in Las Vegas, Nevada. (Photo by Ethan Miller/Getty Images)
Ethan Miller

Youth" was released earlier in the month, and is the third single from Mendes' self-titled third album.

The performance comes after a gunman killed 10 people in a mass shooting at Santa Fe High School in Texas.

"It's a really special performance," Mendes said on the red carpet before the show

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