A 16-YEAR-old boy was among the four workers killed in an explosion at a waste water treatment works in England yesterday.

Michael James (64), Brian Vickery (63), Raymond White (57) and Luke Wheaton (16), died in the incident at Wessex Water’s Bristol water recycling centre in Avonmouth on Thursday.

It is understood that James was a contractor working at the site, while Vickery and White were employees of Wessex Water and Wheaton was an apprentice at the firm.

Bradley Stoke Community School wrote on Facebook: “We were shocked and saddened to hear of the tragic passing of our former student Luke Wheaton yesterday in the Avonmouth tragedy. Our thoughts are with his family and friends at this time.”

Emergency services were called to reports of a large explosion involving one of the chemical tanks at the site at about 11.20am.

The blast happened in a silo that held treated biosolids.

Avon and Somerset Police, which declared a major incident, said a cordon at the site was likely to remain in place “over the coming days” as an investigation is carried out.

This is being supported by the Health and Safety Executive and a team of chemical and mechanical experts, the force said.

Superintendent Simon Brickwood said: “I’d like to extend my heartfelt sympathies to the families of those involved in yesterday’s tragic incident.

An investigation has been launched into the causes of the explosion, with the support of partner agencies and the Health and Safety Executive.

“This is likely to be ongoing for some time and we will be keeping the victims’ families informed throughout.”

Specially trained officers are supporting the family of the four workers who died in the incident.

Formal identification is yet to take place and post-mortem examinations are under way, a force spokesman said.

A fifth person who was injured in the explosion is now at home and investigators will speak to them when appropriate.

Giles Hyder, the Health and Safety Executive’s head of operations in the South West, said: “We send our deepest condolences to the families of those who tragically died. It is important a joint investigation is carried out.

“We will provide specialist support to what is likely to be a complex investigation under the command of the police.”

Witnesses to the aftermath of the explosion described hearing a “boom and echo” which shook the ground, followed by “a lot of commotion”.

Avon Fire and Rescue Service described the scene of the incident as “very challenging”.

Search and rescue dogs were used to identify casualties following the blast.

The explosion is not being treated as terror-related and there are not believed to be any ongoing public safety concerns.