Four people died following an explosion in a silo that holds treated biosolids at a wastewater treatment plant near the southwest England city of Bristol, police said Thursday (local time).
A major incident was declared following the explosion, which happened at around 11.20am this morning (Wednesday 3 December) at at Wessex Water's Bristol water recycling centre off Kings Weston Lane.
Three Wessex Water employees and one contractor died in the incident, which is not being treated as terror-related, Avon and Somerset Police Chief Inspector Mark Runacres said at a media briefing.
Avon Fire and Rescue Service said crews from eight stations were mobilised to respond to the incident and confirmed there had been "multiple casualties on site".
Avon and Somerset Police have said they believe the explosion involved a chemical tank, confirming there had been "a number of casualties".
"There will be a full investigation taking place but, for now, we pay our respects to those who have suffered and lost their lives today".
"A thorough investigation will be carried out into what happened today, involving a number of agencies and the health and safety executive in due course and we will not be speculating on the cause of the explosion while such work is being undertaken", said Runacres.
Fire and police at the scene
A local emergency services department says fire and rescue workers are responding to a report of a "large" explosion at a port near the southwest England city of Bristol.
He said there were no ongoing public safety concerns.
Crews from the fire, police and ambulance services were all in attendance at the site.
"Thank you to the emergency services for doing their very best in challenging circumstances". Six fire engines and rescue dogs were soon on scene.
Jawad Burhan took a photo showing a tank that had exploded after the blast.
Prime Minister Boris Johnson tweeted: "Deeply saddened to learn that four people have lost their lives in the water works explosion in Avonmouth. After ten minutes I saw the helicopter coming and the police", he said.
"This has already been such a challenging year, and this news of further loss of life is another bad blow", said Bristol City Mayor Marvin Rees.