Celsa explosion: No manslaughter charges over deaths
There is insufficient evidence to support gross or corporate manslaughter charges over the deaths of two men in a steelworks explosion.
Peter O'Brien, 51, from Llanishen, and Mark Sim, 41, of Caldicot, died at Celsa UK in Cardiff in November 2015.
The Health and Safety Executive (HSE) is now leading a criminal inquiry into whether health and safety regulations were breached.
Celsa UK said the safety of its employees was an "absolute priority".
The blast happened in the basement of the plant's rod and bar mill, where five men were also injured.
South Wales Police said: "Following a thorough joint investigation by South Wales Police and the HSE, the Crown Prosecution Service found insufficient evidence to support gross or corporate manslaughter charges."
A HSE spokesman confirmed it had taken the lead in the criminal investigation and was in contact with the men's families.
"We have assured them, and indeed make it clear to all affected by this incident, that our investigation will be a thorough one, while also recognising the desire for a speedy conclusion," he added.
Celsa Steel UK said it was continuing to work with the HSE to determine the exact cause of the explosion.
A spokesman said: "We will not rest until this has been established, and are determined that any lessons will be learned.
"Two years on, the loss of two friends and colleagues is still felt deeply by all the Celsa family, and our thoughts and sympathies are always with those most closely affected. We pay tribute to the way our dedicated colleagues pulled together following this most terrible event.
"The safety of employees at all our facilities is our absolute priority, and underpins every aspect of our work."