This is purported to be a recording of emergency calls made after the explosion at the fertiliser plant in West, Texas.
Firefighters were already responding to a fire at the plant when the explosion happened.
A woman's voice can be heard saying: "There has been an explosion on the fire scene, there are firefighters down at this time".
This recording was taken from social media website SoundCloud and all efforts have been made to verify its authenticity, but this cannot be independently confirmed.
A major rescue effort is ongoing in a Texas town devastated by a fertiliser plant explosion that has been likened to a nuclear bomb blast.
A huge explosion at a fertiliser plant in the Texan town of West has injured more than 160 people and caused widespread destruction.