A huge fire has engulfed a 27-storey block of flats in west London, injuring at least 30 people and possibly trapping some residents who were sleeping inside the towering inferno.
Massive flames licked up the sides of the block as 200 firefighters battled the blaze for hours along with 40 fire engines. Flumes of black and grey smoke were billowing high into the air over London hours after the blaze was sparked.
London Fire Brigade said the fire had engulfed all floors from the second to the top of the Grenfell Tower, where several hundred people lived on the Lancaster West Estate.
"We have taken 30 patients to five hospitals," London Ambulance Service said.
An unknown number of residents are trapped inside the block of 120 apartments which is home to about 200 people.
A witness told the BBC that nobody would have been able to escape above the third floor.
"I have watched one person falling out, I watched another woman holding her baby out the window and on the west side of the building hearing screams. People screaming," Jody Martin said, describing the distressing scene said.
Residents related how they woke up to the smell of burning and rushed to escape through smoke-filled corridors.
Nassima Boutrig, who lives opposite the building, said she was awakened by sirens and smoke so thick that it filled her home as well.
"We saw the people screaming," she said. "A lot of people said 'Help, help, help.' The fire brigade could only help downstairs. It was fire up, up, up. They couldn't stop the fire."
London Fire Brigade Assistant Commissioner Dan Daly said firefighters wearing breathing apparatus were "working extremely hard in very difficult conditions to tackle this fire".
"This is a large and very serious incident and we have deployed numerous resources and specialist appliances."
More than 20 ambulance crews were at the scene.
London Mayor Sadiq Khan said a "major incident" had been declared.
Police closed the A40, a major road leading out of west London, while some parts London's underground train network were closed as a precaution.
The cause of the fire, which broke out just before 1am local time, is not known, the Fire Brigade said. Residents said repairs, including the addition of some sort of cladding, had been made to the exterior of the block recently.
