LOUISVILLE, Ky. (AP) — A young couple originally from Tennessee and Kentucky have not been seen since they waved goodbye to the woman's mother at the international airport in Brussels, one of two sites in the city where terrorist bomb attacks killed at least 34 people.

Friends and family of Justin and Stephanie Shults say the couple moved to Brussels in 2014. They said they were dropping Stephanie's mother off and were watching her walk through security when the bombs went off Tuesday.

Relatives say Stephanie Shults is from Lexington, Kentucky, and Justin Shults is from Gatlinburg, Tennessee. They were excited to live in Europe and traveled frequently.

The Islamic State has claimed responsibility for the attacks at the airport and a subway in Brussels that injured hundreds and left scores unaccounted for.