ATLANTA (AP) — Two workers were killed and another seriously injured in an explosion Tuesday at a Delta Air Lines maintenance facility near the Atlanta airport.

Delta said it was working with local authorities to investigate what happened at the wheel and brake shop.

WSB-TV reported that a tire on a plane exploded. The television station cited unnamed sources.

Several Atlanta fire units and police responded to the maintenance hangar near Hartsfield-Jackson Atlanta International Airport shortly after 5 a.m., The Atlanta Journal-Constitution reported. Flights into and out of the airport were not affected.

“The Delta family is heartbroken at the loss of two team members and the injury of another following an incident this morning at the Atlanta Technical Operations Maintenance facility,” Delta said in a statement. “We have extended our full support to family members and colleagues during this incredibly difficult time.”

Delta thanked first responders and medical teams.

“We are now working with local authorities and conducting a full investigation to determine what happened,” the Atlanta-based airline said.

The Federal Aviation Administration said it was in contact with Delta, but referred a request for additional information about the apparent accident to the airline. A spokesman for the federal Occupational Safety and Health Administration, Eric Lucero, said the agency had started an investigation.

The facility where the explosion happened is part of Delta TechOps, which performs maintenance, repair and overhaul work for Delta and more than 150 aviation and airline customers around the world.

The president of TechOps, Delta Executive Vice President John Laughter, said in a note to staff that the airline will make counselors available to employees.

“We’re all in this together, and we’ll get through this by supporting each other,” he said.

Atlanta Mayor Andre Dickens posted on X to offer his condolences to relatives of the victims.

The International Association of Machinists and Aerospace Workers, which is trying to organize 20,000 ground workers at largely nonunion Delta, called on the airline and authorities “to quickly launch a thorough investigation into how this happened.”