Workers at a steel fabrication firm hit by a devastating blaze yesterday came into work today to help with the heart-rending task of clearing up.

But as they searched among charred debris to salvage anything they could - including water-damaged paperwork - Amy Seaman, the PA at Cap Fabrications, vowed they would be back in business on Monday, using unaffected parts of their site in Faraday Road on Great Yarmouth's Harfrey's Industrial Estate.

Ms Seaman said the fire had come as a fresh blow to the 25-strong workforce who were still coming to terms with the company's boss, Stephen Perry, dying suddenly of a heart attack in October.

She said his widow Roberta had resolved to keep the firm going then, and the staff would not let this setback defeat them either.

'The main thing is no one was hurt. It is a great team with many long-serving employees and we will continue through this with the support of our customers,' she said.

Ms Seaman, who has herself worked at the company - established in 1986 - for 14 years, said firefighters had declared the site safe late on Friday evening, but the cause of the blaze had yet to be confirmed.

She said: 'It started in one of our paint spraying booths and we think it is likely it was triggered by an electrical fault there.'

The booth, a neighbouring office and a precision engineering workshop were all devastated by the fire; another unit was smoke-damaged but two further units and the firm's other paint spraying booth were unaffected.

The blaze at the site, which manufactures items such as containers and shipping baskets, triggered a large-scale operation by the emergency services involving 60 firefighters and 40 police officers.

Concern that potentially explosive oxy-acetylene cylinders were present caused police to set up a 200m exclusion zone and order the evacuation of businesses across a wide area of the estate.

All roads into the estate were sealed off leading to serious traffic congestion throughout the afternoon on the A12 and on roads around Yarmouth.

Scores of people had dialled 999 as a large pall of smoke was visible from all parts of the town.

The dramatic suddenness of the fire was described by Trevor Chilvers, a director of neighbouring firm Independent Lifting.

'Black smoke was billowing out of the unit and then flames started coming out of the top of the building. We were worried it would spread,' he said.