Firefighters from stations across Bradford and Leeds are tackling a blaze at Lumb Lane Mills in Manningham.
A total of 15 fire engines were at the scene of the blaze, which started just before 11.30am today.
A West Yorkshire Fire Service spokesman said: “This is a four-storey building used for storage and the fire is in the basement. Four firefighters wearing breathing apparatus are tackling the fire, as well as one hose reel and one large jet.”
Firefighters have been called to the incident from stations at Bradford, Fairweather Green, Odsal, Shipley, Idle, Cleckheaton, Bingley, Illingworth, Morley, Stanningley and Hunslet.