Two workers were killed, and another was seriously injured in a tire explosion at a Delta Air Lines maintenance facility near Atlanta airport on Tuesday.

The explosion occurred while disassembling wheel components at a wheel and brake shop, unrelated to any aircraft.

The cause of the explosion is under investigation by the Occupational Safety and Health Administration (OSHA) and Delta.

The incident did not affect flights or other maintenance operations. Delta expressed heartbreak over the tragedy and is providing support to the victims’ families and colleagues, NPR has reported.

The injured worker remains under medical care, and Delta has made counselors available to employees. The incident has prompted calls for a thorough investigation into the cause.

Written by B.C. Begley