Bristol explosion: 16 year-old boy among four dead in Bristol waste water works incident
Michael James, 64, Brian Vickery, 63, Raymond White, 57, and Luke Wheaton, 16 have been named by Avon & Somerset Police as those who died in the blast.
A fifth person who was injured in the explosion is now at home and investigators will speak to them when appropriate.
Advertisement
Hide AdAdvertisement
Hide AdThe explosion happened at 11.20am on Thursday morning at Wessex Water’s Bristol recycling centre in a silo which treated biosolids.
Avon and Somerset Police said a cordon at the site was likely to remain in place "over the coming days" as an investigation into the cause of the incident was carried out.
This is being supported by the Health and Safety Executive (HSE) 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.
"We appreciate the impact this incident has had on the local community and we thank those affected for their patience while our investigative work is carried out.
"The local neighbourhood policing team is available to address any concerns members of the public may have.
Advertisement
Hide AdAdvertisement
Hide Ad"I'd like to pay tribute to those involved in the emergency response, who have been at the scene throughout the night under very difficult and challenging circumstances."
Formal identification is yet to take place and post-mortem examinations are under way, a force spokesman said.
Giles Hyder, HSE'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."
The explosion is not being treated as terror-related and there are not believed to be any ongoing public safety concerns.