Thirty fire engines and around 175 firefighters tackled a grass fire on Pea Lane in Upminster.
Around 15 hectares of a cornfield and some scrubland was alight, causing smoke to blow over the M25. Around 200 people were evacuated from a nearby caravan site and 60 gas cylinders were removed to a safe area as a precaution as some cylinders can explode when exposed to heat.
The Brigade's 999 Control Officers have taken more than 80 calls to the blaze.
The Brigade was called at 1123 and the fire was under control by 1507. Fire crews from Hornchurch, Harold Hill, Wennington and surrounding fire stations attended the scene as well as colleagues from Essex Fire and Rescue Service.