Emergency services including police and ambulance crews are at the scene.
Officers are advising motorists that there will be disruptions to traffic and if possible they should use alternative routes.
It is not known how many people or how many vehicles are involved.
A police spokesman said: "Please can all local residents be aware of a multiple vehicle road traffic collision on Colne Road, Brierfield. Police and ambulance crews are on the scene and likely to be there for some time. There will be disruptions to traffic so please use any alternative routes."
More details will appear on this website.