BREAKING: Explosion at US airport - several hurt as witnesses report ‘loud boom’

Three people were injured in the blast at Phoenix-Mesa Gateway Airport, which officials say was caused by a build up of natural gas. 

One person has been seriously injured by the blast. All three hurt were private contractors working with the gas. 

Witnesses report heating a “loud boom”. 

Police and fire crews are at the scene. 

The explosion occurred south of the air traffic control tower. 

Compressed natural gas canisters were being transferred when the explosion took place. 

Flights and airport operations have not been effected. 

The airport’s dedicated fire service issued an update on Twitter. 

They tweeted: “3 people injured w/ 1 seriously injured as rslt of explosion south of air traffic control tower; occurred during transfer of CNG (compressed natural gas). Occurred away from runway.”

This is a breaking story, more to follow…