Thornton residents woken by 'explosive bang' and sirens at former ICI site - but what was it?

Families reported hearing an 'explosion' at around 7.30am, followed by the sound of sirens and the wailing of birds.

"That was one hell of a bang in Thornton", said a resident on social media.

"I heard it - sounded like an explosion," added another.

"It was so loud, never heard anything like it! Anyone any idea what's happened?"

The mystery 'explosion', which could also be heard in Fleetwood, has prompted much speculation as to what happened at the site.

Lancashire Fire and Rescue Service said they had not responded to any incidents at the site this morning.

But the Gazette can now confirm that something did happen at the site this morning.

Responding to our query regarding a potential incident at the site, AGC Chemicals Europe have confirmed that an incident did occur.

A spokesman for the firm said: "AGCCE have had a premature failure of a rupture disc at approximately 7.20 this morning.

"This occurred on the ETFE plant on one of the reactors.

"There are no injuries or environmental concerns at this stage.

"Investigations into why this has occurred will be undertaken by the operations team."

What is a rupture disk?

A rupture disk, also known as a pressure safety disc, is a safety device that, in most uses, protects a pressure vessel, equipment or system from overpressurization or potentially damaging vacuum conditions.

Rupture disks are commonly used in petrochemical, aerospace, aviation, defence, medical, railroad, nuclear, chemical, pharmaceutical, and oil field applications.

Has anyone been injured?

AGC Chemicals confirmed that no employees have been injured in the incident and there is no risk to the public.