A HUGE blaze at a recycling plant caused traffic chaos as plumes of smoke billowed over a main road and housing estate.
More than 50 firefighters battled the flames for hours at Enviro Skips in Burnley after 2,000 tonnes of rubbish caught fire.
And even after the fire was out, huge amounts of smoke continued to cause problems for most of the day.
A fire service spokesman later confirmed the fire was not believed to have been deliberately started.
Firefighters were called to the firm off Accrington Road, Burnley, just after 5am on Saturday.
Officers had to cut a hole in the side of a warehouse building to gain access and spent four hours dousing the flames.
But huge plumes of smoke engulfed homes on the neighbouring Valley Gardens estate, where residents were told to keep doors and windows closed.
The smoke also impaired the visibility for motorists on Accrington Road with drivers told to avoid the area for more than 12 hours.
As well as the smoke, the sheer numbers of emergency services vehicles, with eight fire engines and police cars on the scene, led to long delays on the busy road between the M65 and the crematorium.
An investigation was launched on Saturday into the cause of the fire, although it is not believed to have been the result of an arson attack.
Incident commander Dave Jackson said: “We got the call at 5.05am and when we arrived the flames had not got out of the main building but we could see a lot of smoke.
“Because of the large scale of the incident we took water from the canal to take care of the fire.
“We had to create a hole in the side of the building so we could get access to the fire so we prised off some panels so we could get in.
“It was basically a big mound of waste that was on fire and we needed to damp it down and then we could get in to see what was happening inside.”
Firefighters were on the scene for several hours to make sure the fire was out and to then look for clues as to what started the fire.
Fire service spokesman John Taylor told the Lancashire Telegraph yesterday: “At this stage it is not thought to be an arson.
“Firefighters are looking at the possibility it started in a stack of rubbish where there can be a natural hotspot that actually starts a fire itself.”
Bosses at Enviro Skips declined to comment but it is thought the company will reopen today.