Shock at Chevron Pembroke oil refinery explosion deaths
People living near the Chevron oil refinery in Pembroke have told of their shock and sadness at the deaths of four contractors at the site.
A fifth person was critically injured in an explosion during routine maintenance work on Thursday evening.
The plant employs about 1,400 people and those living nearby said most knew people who worked there.
Chevron said it was hugely saddened by the deaths and union leaders expressed their sympathies.
The Unite union has more than 400 members working at the plant and regional officer Allan Card said: "Unite would like to express its deepest sympathy and sincere condolences to the families of those who died and the contractor who was seriously injured.
"It will be a devastating blow to the communities in which they lived."
The union said it regarded health and safety as its highest priority and would fully co-operate with the investigation.
Josephine Watts, 61, of Pembroke Dock, said: "My brother Graham works at the refinery and I worry about him day and night.
"I never know if he is going to come back safely. He has done all sorts of jobs there, from cleaning one of the stacks where the flames come out to driving around the boss.
"He has to go on safety training courses every six months. I think that you cannot do too much from a safety point of view."
Pembroke Dock shopper Bronwen Lewis, 63, said there would never be a guarantee that accidents would not happen.
"There will always be accidents wherever you have a big place like this.
"These places have got to be there at the end of the day and accidents will occasionally happen, no matter what anyone does.
"Unfortunately, in this case, lives have been lost."
Meanwhile, eyewitnesses in the area described the moment when the blast occurred.
'Huge plume of smoke'
Marcus Lutwyche, owner of a shop in the village of Angle near the refinery, said: "I ran to the front and saw a huge plume of smoke. It was black and filled the sky. It must have been 50 or so metres wide."
His wife, Joanne Lutwyche, said: "Quite a few people in the village work at Chevron and would have been changing shifts when the explosion happened, so everyone's really concerned for who might be involved.
"The last time something like this happened must have been about 17 years ago."
Phil Horne, who was in his back garden in Milford Haven, on the opposite side of the waterway, at the time, said: "I heard a large explosion, turned around and saw a large fireball disappearing into the sky.
"It went about halfway up the chimney stack of the refinery."
Liz Herbert, who also lives on the other side of the haven, said: "I heard a massive bang and saw a huge plume of thick black smoke. It was really frightening."