A 10-year-old was killed and three others were injured when a large flight display board toppled over at the Birmingham-Shuttlesworth International Airport.
The accident occurred Friday, only weeks after the flight terminal reopened after a $201 million remodeling.
It took a half dozen bystanders to help lift the approximately 300 pound flight status board and free the four injured family members.
After the accident Luke Bresette, 10, was rushed to Children's of Alabama Hospital, where he was pronounced dead. His mother Heather Bresette is in critical condition at the University of Alabama at Birmingham Hospital. Two other brothers also sustained injuries.
Airport spokesperson Toni Herrera-Bast told the ABC News affiliate ABC 3340 that incident was being investigated.
"We're going to continue to look into the situation, but for now we have secured the site," said Herrera-Bast.
Luke's older sister Anna Bresette has been tweeting about the family's ordeal and wrote that her two other brothers' injuries were not life threatening. She also tweeted that her mother had a broken pelvis and two broken ankles. Friday afternoon she wrote on Twitter, "It still feels like a dream." The family was returning home to Kansas after vacation when the accident occurred.
Birmingham Mayor William Bell released a statement Friday addressing the incident and investigation.
"I have asked our public safety staff to assist this family in their time of need in any way possible as they grapple with what has happened," Bell said.
Although the area where the sign fell was cordoned off, the airport remained open after the incident.
The Associated Press contributed to this report.