A blaze involving 160,000 litres of cooking oil has been brought under control.
Firefighters were alerted to the fire at a storage yard in Little Warley, near Brentwood in Essex, at 5.15am on Tuesday.
Assistant divisional officer Leigh Corke said 65 firefighters dealt with the incident, which also involved 30,000 tonnes of paper and 30,000 litres of diesel.
Utility companies and the Environment Agency were called in by the fire service.
At 10.40am, the fire service issued a statement saying: "Only small pockets of fire remain. Firefighters wearing breathing apparatus are using one hose-reel and one foam branch as they extinguish the final pockets."
At its peak, 15 appliances dealt with the blaze, with fire crews from London drafted in to provide support.
Incident commander divisional officer Mark Samuels said firefighters "aggressively" fought the flames with foam.
He said: "This is a recycling yard that recycles various types of used oils, hence the intensity of the fire."
Once the fire is out, a joint police and fire service investigation will be carried out to establish the cause.