Twenty fire engines and around 125 firefighters were sent to tackle the blaze along with police and ambulances. The London Fire Brigade (LFB) told people to avoid the area. About 150 people were evacuated from the building and police said there were no injuries. Firefighters were still battling the blaze as the sun set after being called at 5.49pm. Authorities did not know what started the fire, but could determine that it started under the floorboards of the Admiralty pub, about 30 meters from Nelson’s Column. The warm weather meant firefighters were working in more intense conditions. The LFB said: “Please think of all the firefighters dealing with fires in these conditions.” Smoke rises in central London (itxjamie/Twitter) Firefighters battle the blaze at the edge of Trafalgar Square (London Fire Brigade) Fire Station Commander Keith McDermott, at the scene, said: “Due to the strenuous, difficult and hot conditions inside the basement we have increased the number of fire engines and firefighters on scene. “Approximately 150 people evacuated the pub and surrounding businesses before the Brigade arrived. There are no reports of injuries.” Photos and videos on social media showed smoke billowing from the building on the south side of London’s central tourist spot. Police warned of heavy traffic on surrounding roads and asked people to avoid the area. Thick smoke covers the street outside the Admiral pub (PA) The fire engine passes Nelson’s Column in Trafalgar Square (LFB) The Mall was closed in both directions between Trafalgar Square and Horse Guards Road. A spokesperson for the Metropolitan Police told the Independent: “Police are assisting with road closures following reports of a fire at an address in Spring Gardens SW1. There are no reports of injuries at this time.”