Massive flames licked up the sides of the block as 200 firefighters battled the blaze for hours along with 40 fire engines. "The fire started on the upper floors ... oh my goodness, it spread so quickly. It had completely spread within half an hour".
"A lot of people said 'Help, help, help.' The fire brigade could only help downstairs". "I've never seen that in a residential block".
These people are missing in the Grenfell Tower tragedy: can you help? "People have been bringing water, clothes, anything they've got to help, out to the cordon".
The cause of the fire was not immediately known.
The tower block was recently refurbished at a cost of £8.7 million, with work completed in May past year.
Samira Lamrani said she saw a woman drop a baby from a window on the ninth or 10th floor to people on the sidewalk.
Tim Downie, who lives not far away, tells Britain's Press Association he feared the block could collapse.
"Every house opened except two - I saw the other guy later on so only 1 family unaccounted for". Tiago Etienne, 17, said he saw about three children between the ages of 4 and 8 being dropped from around the 15th floor.
London police say the death toll in the London tower blaze has risen to 12, and that the figure was expected to rise.
"We have taken 30 patients to five hospitals", London Ambulance Service said.
Other witnesses described a white, polystyrene-type material falling like snow from the building as it burned.
Local councillor Judith Blakeman, who lives opposite the tower, rushed outside when she heard about the blaze at 5am. People who initially remained in place may have been unable to escape later because the hallways and fire escapes were filled with heavy smoke and flames.
"I was just screaming at people: "Get out, get out" and they were screaming back at me: "We can't, the corridors are full of smoke", he told BBC Radio.
"There were people banging on windows screaming, crying out for help".
The Fire Brigade issued a similar notice for another KCTMO-managed building, Hazelwood Tower. It was fire up, up, up.
She said: "Neighbours had been watching it all night, they said the cladding went up like a nightdress by a fire - it just went whoosh".
Footage on social media showed the building engulfed in fire, with flames stretching over a number of floors.
"I'm lucky to be alive. A neighbor's smoke alarm went off and another neighbor phoned and told me to get out", Daffarn said. "I consider this mass murder". The group has raised concerns about testing and maintenance of firefighting equipment and blocked emergency access to the site.
In a blog on November 20, the activist group predicted that only "a catastrophic event" leading to "serious loss of life" would bring the outside scrutiny needed to make conditions safe for residents.
"All our warnings fell on deaf ears, and we predicted that a catastrophe like this was inevitable and just a matter of time", the group said in a blog post Wednesday.
While originally council-owned, in 1996 it was given to the Kensington and Chelsea Tenant Management Organization (KCTMO) to look after and maintain.
Police said "several hundred" people would been have in the building - most sleeping - when the fire broke out.
The sounds of sirens and helicopters is non-stop as locals and residents, evacuated from the building, begin to gather outside to watch the blaze. London Mayor Sadiq Khan said on Twitter that a major incident had been declared.
"The more I looked up, floor upon floor".