AI-restored voice of firefighter killed on duty touches hearts of parents

Bereaved families of firefighters killed in the line of duty cry as they listen to the recreated voice of fallen firefighter Kim Soo-kwang on a T'way Air flight bound for Japan. Screenshot from National Fire Agency's YouTube channel

"Mom! Dad! How have you been? This is Soo-kwang. Are you surprised by my voice? … I miss you a lot. I love you."

This unusual in-flight announcement on a recent T'way Air flight bound for Japan brought passengers to tears as they ate their meals in the cabin.

Among those crying were the bereaved family of Kim Soo-kwang, a 27-year-old firefighter who died in January last year while extinguishing a fire at a processed meat factory in Mungyeong, North Gyeongsang Province.

Restored using LG Uplus' artificial intelligence (AI) technology, Kim's voice was broadcast on a flight carrying 17 parents of firefighters who were killed in the line of duty. The parents were on the way to a four-day trip to Saga Prefecture in Japan, which was organized by T'way and the Fallen Firefighters Survivor Hope Sharing, a foundation for families of deceased firefighters.

In a video clip uploaded to the National Fire Agency's (NFA) YouTube channel on Wednesday, other parents of fallen firefighters were also seen wiping away tears as fellow passengers applauded in support.

"Don't worry. We, as your children, were proud and brave firefighters," the voice said. "Mom, Dad! Even if you can't see me, I'm always with you."

Firefighters salute the photos of Kim Soo-kwang, left, and Park Soo-hoon, who died in January 2024 while extinguishing a factory fire in Mungyeong, North Gyeongsang Province, during their funeral at the North Gyeongsang Provincial Government building in Andong, North Gyeongsang Province, Feb. 3, 2024. Newsis

LG Uplus said Kim's voice was generated using its advanced zero-shot text-to-speech technology, which requires only a few spoken sentences to recreate a specific person's voice. Most AI technologies need hundreds or even thousands of sentences to replicate a person's pronunciation, accent and tone, according to the telecommunications firm.

"We hope that deceased firefighters are remembered as proud children and that we can console their parents," said Lee Myung-seob, head of the environmental, social and governance promotion team at LG Uplus. "We will make a better world with our AI technology and create social value."

The company plans to continue cooperation with the NFA as part of its efforts to use AI to support those who safeguard public safety.