Firefighters are still battling the fire at Grenfell Tower in north Kensington, and it is feared people remain trapped inside the building.
According to CNN, some residents are reported to have jumped from the tower block. Witnesses have also recounted seeing families and children screaming for help and banging on windows.
More than 50 patients have been taken to five hospitals across London.
Witness Jody Martin described the horror blaze to the BBC.
"I watched one person falling out, I watched another woman holding her baby out the window... hearing screams,” she recalled.
"I was yelling at everyone to get down and they were saying 'We can't leave our apartments, the smoke is too bad on the corridors.'"
Michael Paramaseevan also told the BBC that he and his girlfriend and daughter fled from their seventh floor home despite instructions to remain.
"If we had stayed in that flat, we would've perished. My gut instinct told me just to get the girls out. I wrapped the little one up because of the smoke and I just got them out."
It is believed around 200 firefighters, 40 fire trucks and 20 ambulance crews rushed to the scene.