Commissioner of the London Fire Brigade, Dany Cotton said in a televised briefing that there have been a number of fatalities and the number can not be confirmed at this time due to the size and complexity of the building.
Residents said they had warned repeatedly over fire safety in the block.
"Firefighters wearing breathing apparatus are working extremely hard in very difficult conditions to tackle this fire", he said in a post on the brigade's Facebook page. Zara said that she believes he is alright, she thought that he might have broken a bone or two and possibly received some bruises, but the last time that she saw the child, he was alive.
"We declared a major incident very early, which meant not just the fire service but also the London Ambulance Service, the police and the others were involved at the scene", Khan said. "We will cooperate with the relevant authorities and emergency services and fully support their enquiries into the causes of this fire at the appropriate time", the company said in a statement. "A lot of people said 'Help!"
People outside were shouting at firefighters to use more water on the fire as "there are people in there burning to death".
She added: "In my 29 years of being a firefighter, I have never, ever seen anything of this scale". It is managed by Kensington and Chelsea Tenant Management Organisation (KCTMO) on behalf of Kensington and Chelsea London Borough Council.
Sprinklers in the building were reportedly not functional, and signs inside the building told residents to stay in their flats in the event of fire.
Officials did not immediately know what caused the blaze. "We were just standing screaming and they were screaming".
"It is our conviction that a serious fire in a tower block or similar high-density residential property is the most likely reason" for any change in the fire safety standards to occur. "If we had stayed in that flat, we would've perished". The BBC reported that "several hundred" residents could have been at home when the fire started just after midnight.