Kelsea Ballerini paid an emotional tribute to the four Marines who were killed in a mass shooting in Chattanooga on Thursday with a powerful rendition of "Amazing Grace."

The 21-year-old budding country star appeared on Fox & Friends as part of their All-American Summer Concert Series on Friday (July 17), and she took the opportunity to dedicate the song to the victims and the community.

Ballerini has a special connection to the song. "It was the first solo I ever sang," she says.

She also feels a special connection to the people of Chattanooga, since she's a native Tennessean: "I'm from Knoxville, which is super close to Chattanooga, so my heart goes out to them and their families. They're in all of our prayers, I know."

Ballerini was also among the celebrities who posted a photo to social media after news of the shootings broke on Thursday, using the hashtag #NoogaStrong. "I just think it's important to show our support and show our love," she says. "They feel it, you know."

The singer-songwriter delivered an impassioned acoustic performance of the gospel standard that had the audience transfixed, with a simple, yet very effective electric guitar solo inserted. Some of the crowd sang along with her as she drove home the song's message of the power of love and redemption.

According to CNN, 24-year-old Mohammad Youssuf Abdulazeez fired shots at a recruitment office in a strip mall before moving on to attack a Naval Reserve center, where he killed four Marines. The shooter was killed in the attack, which is being investigated by the FBI.

Kelsea Ballerini + the Other Best Songs of Summer 2015

Kelsea Ballerini Talks About Her First Times