KNOXVILLE, Tenn. (WATE) – A U.S. Army soldier from Corryton was one of 13 American service members killed in an attack outside Kabul’s airport Thursday, according to his family.

Army Staff Sgt. Ryan Knauss was a graduate of Gibbs High School. Knauss’s grandfather Wayne Knauss said Friday that the 23-year-old was among the fatalities when a suicide bomber and gunmen attacked Thursday outside Kabul’s airport during the evacuation of American forces and allies.

“He grew up in a Christian home, attended Berean Christian school through eighth grade and spent, four years at Gibbs High,” Wayne Knauss said of his grandson. “A motivated young man who loved his country. He was a believer so we will see him again in God’s heaven.”

Stepmother Linnae Knauss said Ryan was looking forward to coming back to the states and moving to Washington, D.C.

“He was a super-smart, hilarious young man,” she said.

Knauss said his grandson served for five years with special training in psychological operations. The family received word Friday morning. Funeral services will be shared once they are planned.

Elected officials released statements following the announcement of Knauss’ death.

“Ryan embodies American heroism — saving people he had never met before, in the face of persistent evil. We will never forget his sacrifice in service to his country. While no words could ever be enough, I join Tennesseans — and all Americans — in extending my deepest condolences to Ryan’s family. Chuck and I are praying for them during this time of unimaginable pain and loss.” Sen. Marsha Blackburn said.

“Ryan gave his life outside that airport helping people he didn’t know get to safety. This is what true heroism looks like and Ryan’s sacrifice will never be forgotten. The Knauss family is in my prayers.” tweeted Rep. Tim Burchett, of Knoxville, who represents Tennessee’s Second Congressional District.

The attacks killed at least 60 Afghans and 13 U.S. troops, Afghan and U.S. officials said. Eighteen service members were wounded and officials warned the toll could grow. More than 140 Afghans were wounded, an Afghan official said.

President Joe Biden vowed to finish the evacuation efforts and avenge the deaths of American servicemembers in an address to the nation Thursday evening, declaring to the extremists responsible, “We will hunt you down and make you pay.”

Secretary of Defense Lloyd J. Austin III issued a statement expressing his deepest condolences for the military members who died in the attack.

Marine Gen. Kenneth McKenzie Jr. said Thursday the military believes the complex attack outside Kabul airport was carried out by ISIS-K, a splinter group of the terrorist group ISIS, adding the military will “go after” the perpetrators of the Kabul attacks if they can be found.

“We expect these attacks to continue,” he said, adding that Taliban commanders have been asked to take additional security measures to prevent another suicide bombing on the airport’s perimeter. He said he sees no indication that the Taliban allowed Thursday’s attacks to happen.