SANTA ANA (CBSLA) — A worker was killed at John Wayne Airport late Tuesday night when the 4-foot-tall tire he was working on exploded.

The bizarre accident happened in a workshop under Gate 3 at the airport at about 11:30 a.m. as two people were repairing the giant tire on a jet bridge, the walkway that connects the terminal to the plane.

One worker was on top of the tire, and the other on the bottom, when it exploded. One of the workers was killed instantly, while the other walked away without injuries.

The force of the explosion caused a pipe to burst and set off the sprinklers in the workshop, but otherwise did not affect the operations of the airport.

The worker who died has not been identified. The two workers were not employees of the airport, but of a contractor called JBT, which said they are fully cooperating with the investigation into the accident.

“We are deeply saddened by this event, and are focused on providing support and assistance to our employees and their families,” the company said in a statement.

Cal OSHA is expected at the airport Wednesday morning to launch an investigation, which could examine whether the tire was faulty or there was an issue with the repair.