A major investigation is underway into the cause of a huge blaze at a mill building which brought the city centre to a halt.

Up to 80 firefighters tackled the fire off Thornton Road, near to its junction with Tetley Street, which broke out during Tuesday's rush hour at the disused mill.

A black cloud of smoke descended upon the city centre as the fire took hold of the five-storey building, causing its roof and several walls to collapse.

Burning embers were thrown into the air, falling on to roads filled with cars and crowds of on-lookers as shoppers and workers tried to make their way home.

Emergency services swiftly evacuated The Jury’s Inn Hotel after flames began to shoot out of the windows and roof of the mill building.

Police meanwhile had to cordon off roads surrounding the fire, including large parts of Thornton Road and Sunbridge Road, to allow firefighters to get the fire under control and protect nearby buildings.

One nearby property owner, who did not want to be identified, said: “We were in our building and we heard crackling and we thought somebody was in our building.

“And then my friend looked across and saw the other building was on fire.

“The fire was at first just coming out of a couple of windows and then within seven minutes or so the whole building was up,”

His friend, who also did not want to be identified, said: “Within four or five minutes it was an inferno.”

On-lookers said the building was believed to have been empty but regularly used by squatters.