FIRE ripped through a warehouse on an Alton industrial estate on Sunday, gutting one unit and damaging another. More than 100 firefighters tackled the blaze in the RiverWey Industrial Estate in Newman Lane, some spending four-and-a-half hours at the scene. The roof of the unit and its contents, sport and recreational equipment housed there by tenants 3C Leisure, were completely destroyed by flames, while neighbouring business Absolute Aroma found the dividing wall had buckled into its premises. Fire services were alerted when a smoke alarm in the Absolute Aroma office was triggered just before 5 pm. Twelve fire pumps were on the scene soon after, along with two aerial ladder platforms and two water carriers. Fire quickly took hold of the building, with flames and plumes of thick black smoke billowing through the roof. Metal cutters were used to make holes through which hoses were directed, but the site was considered too dangerous for firefighters to enter. Officers on aerial platforms also poured water over the flames after parts of the roof caved in. Alton fire station chief Graham Howlett said: "We knew there were no people inside, but there was a threat of explosion from two gas cylinders on a forklift truck. "So we decided to fight the fire defensively from the outside until it was sufficiently contained." The fire was completely extinguished and the area declared safe by 9-30 pm. Run-off water also had to be pumped off roads and out of drains to avoid contamination of the nearby River Wey. A full investigation is under way, but early indications point to an electrical fault rather than arson. James Mayl watched the fire grow from outside his home in Adams Way, on the other side of the railway track. He said: "I saw smoke coming from the building when I got home. There were no firemen there yet, but several people standing around. "After the fire trucks arrived I could hear voices on a megaphone from my house. "At first it seemed like they had it under control but later, about 6-20 pm, the voices sounded panicked so I went to the train station car park to take a look. "It looked like part of the roof had collapsed, and the smoke had gotten worse; it went from hazy white to thick and black. "I went back again at 7-30 pm and I could see white smoke but no flames. There was still one fire crew there cooling the building." Barnaby Foster, manager of 3C Leisure, described the unit as "just shrapnel" although Edward Martin of King Sturge property consultants, representing the landlord, said the fate of the building would be decided at a meeting of loss adjustors today (Friday). Next door in Absolute Aroma's premises, smoke and water damage has left bottling machinery unusable and the buckled wall has made a mezzanine floor unsafe. Professional cleaners were called in yesterday to see what could be salvaged, and the company plans to be open for business on Monday in an unit opposite which has just been vacated. Kay Tomlinson, who helps her husband David run the business, said: "It was a nightmare. My husband was the first to be told about the fire, but he was at a trade show in Las Vegas and had to get someone else out. "Most of our stock was on the other side of the building, but lots of packaging was affected by smoke. "We have tried to save what we can but because we sell to retailers we cannot send any damaged goods so it's impossible to say how much we have lost yet. "But we have to keep going and carry on doing business."