Six fire engines and around 40 firefighters tackled a fire at a recycling centre on River Road in Barking.
Around 100 tonnes of waste was alight. There were no reports of any injuries.
Leading Firefighter Peter Carter, who was at the scene, said: “The fire was discovered by a passer-by who could see smoke coming from inside the yard.
“Crews worked quickly to bring the fire under control and damp down remaining hot spots with the assistance of an on-site digger which helped to turn over the rubbish.”
The Brigade was called at 0335 and the fire was under control by 0443. Fire crews from Barking, East Ham, Plaistow and Ilford fire stations attended the scene.