Two quick-thinking security guards at the Oxford Castle site stepped in to stop a blaze spreading throughout the £34m hotel, leisure and heritage complex.

The development, off New Road, will feature a Malmaison hotel and luxury flats when it launches later this year.

Riaan van Rooyen and Gordon Crichton But firefighters said it could have gone up in smoke yesterday -- had it not been for security staff Gordon Crichton and Riaan van Rooyen.

Mr Crichton, 20, discovered smoke coming from a construction workers' drying room, in part of the former Oxford Prison buildings being converted into the hotel.

He said: "As soon I opened the door the smoke and heat shot over my head and I could see the flames inside. Riaan and I got six fire extinguishers from around the site and started to tackle the fire.

"We did our best but it wasn't going out so we called the fire brigade and they arrived within minutes.

"I'll be delighted if this means a pay rise."

Incident commander Richard Bowley, who led a team of more than 20 firefighters, said the security guards' swift action had "gone a long way towards preventing the fire from spreading and potentially causing a larger fire".

He said: "We think the fire may have been started by a microwave oven or something near it and an investigation is continuing to discover the cause."

The multi-million-pound development is being run by the Trevor Osborne Group and Oxfordshire County Council.