The investigation into the deaths of two men in an explosion at a former steelworks site in South Bank four years ago will now be led by the Health and Safety Executive (HSE), it has been confirmed.

John Mackay and Tom Williams died following a blast at what is now the Teesworks site, on September 19 2019.

They were three weeks into a six-week contract to strip furniture from the towers to prepare them for demolition, when the disaster happened at the site, which was under the control of the South Tees Site Company, a central government body, at the time.

The HSE said, following a thorough joint investigation by Cleveland Police and HSE, there is "insufficient evidence to support gross or corporate manslaughter charges".

The families of the deceased have been informed of this decision.

Read more: Two people confirmed dead were on cherry picker when explosion tore through steel plant

The Northern Echo:

HSE principal inspector John Heslop said: “Although some of these developments are difficult for the families of John and Tom, I have assured them that the criminal investigation into their deaths remains ongoing.

“We also made it clear our investigation will be a thorough one, while also recognising the desire for a speedy conclusion.”

This remains a criminal investigation that Cleveland Police will continue to support.

Fire crews attended the SSI site in South Bank, Redcar, after a blaze broke out on the premises.

Read more: Tributes paid to men who died at former SSI site

The blast appeared to have engulfed the two workers who were on a blue cherry-picker at the time, working at a height.

It looked to have happened as they worked on large pipes near a gas holder, it was reported at the time.The Northern Echo:

Tributes were paid to both men at the time.

Mr Mackay, 49, of Edinburgh, was a husband, father, step-father and grandfather who was described by his family as a "much loved" person.

His family said: “John was much loved by his wife, parents, sisters, children, stepchildren and grandchildren and will be greatly missed by his family, friends and colleagues.

"We are immensely grateful for the support we have received in the past week and take comfort in hearing how popular a man John was.”

Read more: Memorial for 'much-loved' men killed in Redcar SSI blast marks year anniversary

The second man involved in the incident, Mr Williams, 65, of Warwickshire and father to Emma and grandfather to Jordan, Kade and Jazmin was described by his wife Bobbie as "dearly loved".

Paying tribute Mrs Williams said: “Tommy was a dearly loved husband, father and grandfather who will be desperately missed.

"I would like to send all my gratitude and thanks to every member of the team that has been involved. I cannot thank you all enough.”

The Northern Echo:

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The contract workers, one from the demolition firm John F Hunt, who are the main contractors at the site, and the other from Nationwide Platforms, which provides the cherry pickers, were removing the furniture from the outside of the tower stack, when the explosion happened.

A spokesperson for the South Tees Site Company, said: “Our thoughts remain with loved ones of John Mackay and Tom Williams following this tragic and devastating incident almost four years ago. We have always fully supported the need for an extensive and detailed investigation into this tragedy and the process to provide important answers to the families.

“We will continue to work with the Health and Safety Executive to provide all and any assistance required with the investigation as it progresses to a conclusion.”