More than 70 firefighters fought the blaze at the Dawn Pac plant as plumes of acrid black smoke rose several hundred feet into the air.

Firefighters fought to contain the blaze

About 160 staff were at the factory alongside the A48 dual carriageway in Cross Hands when the fire broke out.

No one was injured in the blaze but eyewitnesses reported loud explosions as the single-storey building disintegrated.

The company is the second largest employer in the area and it is not known yet what will become of the jobs at the factory.

Meanwhile the clear-up operation continued on Thursday and public protection officers from Carmarthenshire County Council monitored for pollution.

Council officer Phil Davies said: "They have been monitoring in case of pollution from the fire or a danger from any chemicals stores at the site.

The company is a major employer in the area

"No evacuations have been necessary and the site is still being monitored."

As a precautionary measure police asked local residents to stay indoors and keep their windows closed.

The fire started at about 2000 BST and five fire appliances were still at the scene on Thursday morning damping down.

A member of staff, who didn't want to be named, said: "It is very upsetting to everyone.

"The fire drill worked okay."

The Irish-owned company has another facility in Wales at Pontardawe near Swansea.

Large employer

Dawn Pac is one of Europe's leading food processing companies and employs 250 people at the Cross Hands plant.

The firm is the second largest employer in the Ammanford area.

It processes and packages 300 tonnes of meat every week for leading supermarkets across the UK.

Ranges include Welsh branded beef, lamb and organic meat.