A huge fire has broken out at a Grade II listed building in Keighley.
Footage on social media shows flames engulfing Dalton Mills in the town centre.
West Yorkshire Fire and Rescue Service says more than 20 crews and over 100 firefighters are on the scene, along with an aerial ladder from Bradford.
The blaze started on the ground floor and has spread throughout the building.
There are no reported injuries.
West Yorkshire Fire and Rescue says there is a risk of collapse at Dalton Mills
West Yorkshire Police is urging people living nearby to keep their windows and doors closed and say people should avoid travelling to the area.
The police, ambulance, Yorkshire Water and Environment Agency are all on the scene and road closures are in place around the area.
Dalton Mills dates back to the 19th century and was once the largest textile mill in Yorkshire, employing over 2,000 workers.
It has since been used as a filming location for many TV series such as The Great Train Robbery, Peaky Blinders and Downton Abbey.
Bradford Council has set up a rest centre in the town's leisure centre for people affected by the fire.
Keighley & Ilkley MP Robbie Moore said the fire is "extremely concerning" and has thanked the emergency services.