Developer Multi has restarted work on its £360 million SouthGate site ahead of schedule after a major fire.

It was not expected to send workers back onto the city centre site until tomorrow but construction was under way again this morning.

The firm says initial indications suggest damage to a block of shops at the construction site is only "minor".

Hundreds of construction workers returned to the nine-acre site at 7.30am today - little more than 36 hours after gas canisters exploded on the roof of the largest retail block on Tuesday.

A spokeswoman for Multi said the site was now largely operational and the area where the incident occurred had been isolated.

She said today: “This isolated area will resume production when all necessary investigations have been completed.

“A full survey is being carried out over the next few days to ascertain the complete extent of the damage, however initial indications suggest the damage is relatively minor.

“It is hoped the timetable will not be substantially affected, however this cannot be confirmed until the results of the survey are fully known.”

This week’s explosion occured during roofing work on one of three retail and residential blocks due to open as part of the first phase of the development in Autumn 2009.

Multi bosses will be meeting with representatives of contractor Sir Robert McAlpine and Bath and North East Somerset Council in Bath tomorrow to discuss the best way forward with progress at SouthGate.

Scores of people were evacuated from their homes on Tuesday night after the blaze brought the city centre to a standstill.

Emergency services had to close a large section of the heart of the city after the fire in an asphalt burner on the roof of block B at the development.

Fire officers and specialists from oxygen firm BOC removed the last two gas cylinders yesterday lunchtime.

A spokesman for Avon Fire and Rescue Service said: “The site has now been handed back to site personnel."