More than 100 firefighters have been battling a large blaze on an industrial estate in northwest England.
Huge flames were seen shooting into the night sky at the Enterprise Business Park in Leyland, Lancashire, which is home to a number of businesses and warehouses.
Between 130 and 150 firefighters were called to the blaze, manning eight fire engines, two aerial ladders and a high-volume water pump.
The force's area manager, Keith Marsh, told Sky News: "The long term effects of this, in terms of pollution, have as far as we possibly can, been kept under control."
It is thought a 80,000m sq building that houses tissue paper initially caught fire and flames spread rapidly to a neighbouring building, storing chemicals.
Local reports also suggested explosions could be heard coming from the blaze. Twenty homes were evacuated but a technical support team deemed the chemicals not to be harmful.
Trains between Preston and Wigan North West and Bolton have been hit by delays of up to two hours because of the fire, according to National Rail.
Lancashire Police were first called just before 5.20pm on Wednesday and a cordon was put in place on local roads, with motorists warned to avoid the area.
A police helicopter used thermal imaging to help find the hottest parts of the blaze to assist fire crews.
People living close to the site have also been warned to stay indoors and keep windows closed due to the amount of smoke in the area.
A police spokesman said: "A cordon has been put in place and a number of roads have been closed in the immediate area.
"As such we are asking people to avoid the area if possible this evening. People living close by are being advised to keep windows and doors closed due to the amount of smoke in the area.
"We would like to reassure people that at this time there is nothing to suggest anybody is any danger."