Firefighters say they're allowing a fire at a waste depot in Swindon to burn itself out.
Crews were called to the Cheney Manor industrial estate last night and are still at the scene.
The smoke isn't toxic but residents and motorists have been advised to keep their windows shut as a precaution.
Crews from Wiltshire Fire & Rescue Service are still damping down after 750 tonnes of building and timber recycling material went up in flames last night.
There are now eight fire engines in attendance at the industrial site in Swindon where a fire is blazing at a waste depot.
Firefighters say they're trying to create fire breaks around the affected area on the Cheney Manor estate.
Smoke from the fire can be seen from some considerable distance and the Environment Agency and Public Health England are monitoring the site
– Public Health England
People should do all they can to stay out of the smoke.
If residents are affected by smoke, they should stay indoors and keep windows and doors closed.
Motorists who have to travel through the smoke should also keep windows closed, turn off air conditioning and keep their air vents closed.
Anyone affected by the smoke or concerned about its impact on their health should call NHS 111.
The site is next to the main railway line. Trains are now running through the area but are described travelling under caution.
Wiltshire Fire & Rescue Service is expecting to be at the scene of a significant fire in Swindon for much of today.
Crews were called to Swindon Skips in Brindley Close, on the Cheney Manor Industrial Estate shortly before 9pm last night. On arrival, they found 750 tonnes of building and timber recycling material well alight.
Six fire engines initially attended, from Westlea, Swindon, Stratton (two), Cricklade and Marlborough, supported by the aerial appliance from Swindon, water carriers from Royal Wootton Bassett and Pewsey, and an incident command vehicle from Stratton.
Smoke from the fire can be seen from some considerable distance away - air quality is being monitored by Public Health England and people living locally are advised to keep windows and doors shut as a precaution.
The site is adjacent to the main railway line – trains were stopped for a time overnight but are now travelling through under caution.
A fire investigation will be carried out in due course. As yet, it's not known how the blaze started.
We will be fighting the fire on Cheney Manor Ind Estate, #Swindon for some hours yet - keep windows shut if you're worried about the smoke.
More than 40 fire fighters are tackling a major fire at a waste depot in Cheney Manor in Swindon.
A 750 tonne pile of broken wood is alight at a skip company. The fire - which is not toxic - is still burning and residents are being advised to keep windows closed.
No-one is thought to have been hurt.