Massive Industrial Fire and Fertiliser Explosion in Rettendon, Essex

A major incident was declared and more than 100 firefighters were sent to tackle a massive fire which ripped through an industrial unit and caused a huge explosion, triggered by a store of fertiliser. Footage which captured the moment of the explosion showed a ball of flames erupting into the air and people fleeing, while witnesses told BBC News the sound was "like a bomb" and as loud as a "sonic boom". A number of buildings and vehicles on farmland were gutted by the fire, which kept burning into Saturday. The cause of the fire was being investigated, the fire service said. People living near the fire - which happened close to the village of Rettendon, south of Chelmsford - were urged to keep their windows closed as smoke spread. As of Friday evening, it was not clear whether there had been casualties, but in an update that night, Dave Bond of Essex County Fire and Rescue Service said: "While on the scene, fertiliser inside one of the units exploded and residents across the county have reported hearing and feeling it. "This is why we declared a major incident, and I want to reassure our residents that there is no wider risk to the public at this time." He said "everybody at the scene is safe" but that residents have been evacuated. The fire service said the response was scaled down, with about 25 firefighters on scene as of 08:00 BST on Saturday as well as specialist officers and advisors to extinguish the rest of the blaze. Crews are expected to remain on site for the rest of Saturday, and smoke is still coming from the scene, the fire service added. East of England Ambulance Service said its hazardous area response team and the police were also in attendance. Earlier on Friday evening, Bond said there was still "significant smoke" at the scene, but he believed that the fire had been "surrounded". Sam Dimond, whose event production company Spotlight Sound is based at the site, said he was "currently assessing the impact on our premises and equipment". "Our first thoughts are with everyone impacted by the fire, and we would like to thank the emergency services for their incredible work in bringing the situation under control," he said. "Our priority is the safety and wellbeing of our team, all of whom are safe and accounted for." He previously said lots of people's units had "gone" after the blaze tore through the industrial site. Locals reported hearing the explosion on Friday afternoon. Matthew Fergusson, from Wickford, described a "massive explosion" that sent a "mushroom cloud" towering into the sky. "I thought someone had dropped something heavy upstairs, but when I went outside the whole street was out," he added. Steven Whan, 58, from Bicknacre, near Danbury, thought he had heard a jet's sonic boom when the explosion occurred. "Our house shook, the doorbell went off. I thought it was a sonic boom because we've experienced that before," he said.