The blaze broke out in the early hours of Tuesday morning at the Ainscough Mill site in Burscough.

The Grade II listed mill is being converted into 56 apartments.

Work started more than a year ago and was due to be completed in September 2014.

In a joint statement, Christopher Sheelan, head of support services for Askam Construction, and Mark Cook, managing director of Persimmon Homes Lancashire, said: “Firstly, we would like to thank Lancashire Fire and Rescue Service for their speedy response to the fire at Ainscough Mill.

“The Mill is an iconic feature of Burscough, and a reminder of the village’s industrial heritage, so this fire is desperately sad for everyone in the area.

“Askam Construction, of Lancaster, are currently in the process of converting Ainscough Mill into 56 apartments, delivering the design and build project on behalf of Persimmon Homes.

“These were due to be completed and available to local people in September 2014.

“It is likely to be a few days before we are able to establish the cause and extent of the damage but both companies have offered their full co-operation to the fire service and police as they investigate the fire.”

Lancashire Fire and Rescue said over 50 firefighters fought the blaze for more than five hours.

It added: “The cause of the fire is currently unknown and an investigation has begun.”

How the scheme is due to look