An American husband and wife remained missing more than 24 hours after deadly blasts rocked Brussels, family members told NBC News.
Justin and Stephanie Shults had just dropped off her mother at the Belgian capital's airport when two blasts killed at least 11 people in the check-in lounge.
"Her mom is fine but no one has been able to contact Justin or Stephanie," Justin Shults' brother, Levi Sutton, told NBC News late Tuesday. He added that the State Department told him Tuesday afternoon that the pair were not on any casualty list and both their phones were going straight to voicemail.
Justin, 30, is originally from Gatlinburg, Tennessee, while 29-year-old Stephanie is from Lexington, Kentucky, but moved to the Belgian capital in 2014, Sutton said.
Both work as accountants — Stephanie for the global food giant Mars, and Justin for Clarcor, a Franklin, Tennessee-based firm that makes filtration systems and packaging products.
The couple had parked their car and waved goodbye to Stephanie Shults' mother, Carolyn Moore, who was heading toward security when the blast happened, according to Moore's sister, Betty Newsom.
"She doesn't know ... if Justin and Stephanie watched her as she headed towards security or if they turned to leave the terminal. She doesn't know," Newsom told NBC affiliate WLEX. "We don't know for sure if [they] had been able to get out of the airport or if they were still in the airport."
She said the U.S. Embassy in Brussels has been in contact with them, and Stephanie's employer Mars was also involved in the search.
"All they can really do is go from hospital to hospital looking at the list of people that have been identified as injured," Newsom said, adding that the mother was "of course very frightened and very worried about her daughter."
State Department Spokeswoman Pooja Jhunjhunwala said she had "no updates at this time" when asked about the missing couple.
"The situation is still fluid, but we are working with local authorities to locate and assist any U.S. citizens affected by the attacks," she said in an email.
At least eight Americans were believed injured in the attacks, including three Mormon missionaries, a U.S. service member and four of his family members.
The suspected suicide bombers were named early Wednesday as Khalid El Bakraoui, 27, and his 30-year-old sibling Ibrahim
