Firefighters tackling blazes which have ripped through homes and buildings in London have described the conditions as "absolute hell" on what is the UK's hottest day on record. Residents were evacuated, people were taken to hospital and a major incident was declared by the London Fire Brigade (LFB) which was "under immense pressure" after a "huge surge" in blazes across the capital as temperatures topped 40C (104F) for the first time.