Brantley Gilbert says he didn't write a new song called "Gone But Not Forgotten" for the members of the U.S. Armed Forces killed in Kabul, Afghanistan, last week, but he hopes it resonates with those needing to hear it.

The singer dropped this unreleased track on his Instagram page on Saturday (Aug. 28), two days after 11 Marines, one Army Staff Sgt. and one Navy medic were killed in an attack at the airport in Kabul (per NPR).

Recognizing the tragic loss of life, Gilbert says, "13 brave American heroes made the ultimate sacrifice for freedom this week. In hard times like this, I always find myself turning to music. I wrote this song a while back as a tribute to all of the folks we’ve lost, both overseas and in our own communities here at home."

"(I) Wanted to share it with y'all in hopes it might resonate with someone who needs to hear it right now," the 36-year-old says in closing.

"Gone But Not Forgotten" is a fully-produced country-rocker that looks back on a variety of memories, including those who died too young. This is certainly not the first time Gilbert has written and released a dedication to the military.

"One Hell of an Amen" became a No. 1 hit in 2015 after the singer and his co-writers were inspired by the overseas death of Jonathan E. Lootens. The writers didn't know Lootens, but Gilbert knew Army Ranger Josh Greene well. Greene watched Lootens die in a bombing and was there to hold his hand during his final moments. For years Greene battled demons because of this event, until getting to meet Lootens' family for the first time. That moment was orchestrated by Gilbert.

Also in 2015, Gilbert joined a motorcycle ride for the Wounded Warrior Project. At the end, Staff Sgt. Justin Patterson gave Gilbert the Purple Heart he had earned, telling him how "One Hell of an Amen" had made a difference in his life. Since then, Gilbert has been supportive of a number of military charities and initiatives and kept in close contact with men like Patterson.

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