Fifteen fire engines and around 100 firefighters were called to a fire at a factory with around 400 tonnes of waste recycling alight, in west London.
London Fire Brigade said that it received a call at 11.41pm of the blaze at the factory on Rigby Lane in Hayes where a huge amount of waste recycling is in flames.
Around 10 gas cylinders, which could have exploded in the heat, have been removed from the factory.
The fire service stated: "Fifteen fire engines and around 100 firefighters have been called to a fire at a factory on Rigby Lane in Hayes.
"A factory containing around 400 tonnes of waste recycling is alight. Around 10 gas cylinders have been removed as a precaution as some cylinders can explode when exposed to heat.
"The Brigade was called at 2341. Fire crews from Hillingdon, Heathrow, Feltham, Hayes, Heston and surrounding fire stations are at the scene.
"The cause of the fire is not known at this time."
Station Commander Dean Wilkinson, at the scene, said that there are currently no reports of injuries.
Images from the scene show ladders being used as "water towers" to get water onto the building.
Commander Wilkinson said: "Firefighters are working swiftly to bring the fire under control. There are currently no reports of any injuries.
"Two of the Brigade's 32-metre turntable ladders are being used at the scene as water towers, to get water on to the building externally.
"Around 10 gas cylinders have been removed as a precaution as some cylinders can explode when exposed to heat."
People have taken to social media to comment on the huge emergency services response and the number of sirens being heard.
One person tweeted: "Can hear loads of sirens and what sounds like fire engine sirens at the moment - hope it's nothing serious."
Another wrote: "Really toxic, be careful."
The fire brigade tweeted just after 3am: "Firefighters are making steady progress at the fire in #Hayes and are expected to remain at the scene throughout the night. Crews have removed around 10 gas cylinders as a precaution as some cylinders can explode when exposed to heat."
And a later tweet said the fire had been brought under control: "The fire at a factory in #Hayes is now under control, but firefighters remain at the scene. There are currently no reports of any injuries."
