Chevron oil refinery blast: No manslaughter charges
There will be no corporate manslaughter charges after an explosion killed four workers at an oil refinery in Pembrokeshire in 2011.
Julie Schmitz, 54, Dennis Riley, 52, Robert Broome, 48, and Andrew Jenkins, 33, died in the blast at the Chevron refinery - now Valero - on 2 June 2011.
The Crown Prosecution Service (CPS) has now said there is insufficient evidence to pursue charges against companies.
Families have been informed of the decision.
Dyfed-Powys Police said the four-year inquiry was "extremely complex" and "left no stone unturned".
An investigation will be continued by the Health and Safety Executive.
The deaths happened when a 160,578-gallon (730,000 litres) storage tank exploded, damaging a vessel next to it.
A fifth person was also seriously injured in the blast.
At the time of the incident, the refinery was operated by Chevron, although a deal had already been struck to sell the plant to Valero.
When the police investigation was at its height in 2012, Dyfed-Powys Police said inquiries had been made with in excess of 1,800 potential witnesses with over 200 providing statements.
A spokesman for Chevron said: "Everyone at Chevron remains profoundly saddened by the loss of lives. We continue to remember those individuals, families and colleagues affected by the incident.
"The investigation being conducted by the Health and Safety Executive is on-going and both Chevron and Valero continue to provide their full support and cooperation.
"Chevron remains deeply committed to the safety of employees, contractors and the communities where we work, and we strive continually to work safely."