A massive blaze has engulfed a block of flats in west London, with witnesses reporting people being trapped in their homes.
More than 200 firefighters were sent to tackle the fire at the 27-storey Grenfell Tower which was reported just after 1.15am this morning.
Police said a 'number of people are being treated for a range of injuries', including two for smoke inhalation, as pictures from the scene in north Kensington showed flames engulfing the block and the plume of smoke visible across the capital.
Six people have died in the Grenfell Tower fire but the death toll is expected to rise, Scotland Yard said.
Thirty people have been taken to five hospitals, London Ambulance Service said.
Witnesses described screams of terror and people jumping in a bid to reach safety after the blaze ripped through Grenfell Tower.
Others spoke of safety concerns and the panic sparkled by unfounded fears terrorism could be to blame for the disastrous fire.
One witness described hearing a neighbour screaming for help before apparently jumping out as flames engulfed his seventh-storey flat.
Speaking from an evacuation centre on Freston Road, the woman, who asked not to be named, told the Press Association: 'We were being evacuated from Testerton Walk, which is next to Grenfell, at about 1am, at that point it looked like just one side of the building was on fire, but within about 40 minutes we could see at least three sides were burning.
'There was a woman stood behind me who was shouting to someone she knew on the seventh floor.
'She was on the phone trying to speak to him, she was obviously very emotional because the flats were blazing at this point.
'He looked like he was screaming to her.
'Police said for anyone at the windows to wave a rag or something so the firemen could rescue them, but we thought: how are they gonna do that?
'I saw the woman later and she was hysterical.
'She said her friend jumped. The whole of his window was on fire.'
She added: 'Everybody was crying. Nobody really knew what was going, or what is happening from now on.
'Where do people go? People have been saying the whole building could collapse at any stage. So frightening.'
Fire crews from north Kensington, Kensington, Hammersmith and Paddington and surrounding stations were at the scene with the fire burning from the second to the top floor.
The cause of the fire is not known at this stage, London Fire Brigade said.
Fabio Bebber wrote on Twitter: 'More screams for help as the fire spreads to another side of the building.
'We can see how quick the fire spreads via the external panels. It's unbearable hearing someone screaming for their lives at Grenfell tower.'
George Clarke, who presents the Channel 4 TV show Amazing Spaces, told Radio 5 Live: 'I was in bed and heard 'beep, beep, beep' and thought, 'I'll get up and run downstairs as quickly as I could'.
'I thought it might be a car alarm outside and saw the glow through the windows.
'I'm getting covered in ash, that's how bad it is. I'm 100 metres away and I'm absolutely covered in ash.
'It's so heartbreaking, I've seen someone flashing their torches at the top level and they obviously can't get out.
'The guys are doing an incredible job to try and get people out that building, but it's truly awful.'
London Fire Brigade assistant commissioner Dan Daly said: 'Firefighters wearing breathing apparatus are 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.'
London Ambulance said it had sent a 'number of resources' to the scene, including its Hazardous Area Response Team.
London mayor Sadiq Khan tweeted: 'Major incident declared at Grenfell Tower in Kensington' and urged people to follow London Fire Brigade on Twitter.
Stuart Crighton, London Ambulance Service assistant director of operations, said: 'We have sent a number of resources to the scene including our hazardous area response team and over 20 ambulance crews.
'Our priority (is) to get people to safety and ensure they receive the medical help as quickly as possible.
'Our initial priority is to assess the level and nature of injuries and ensure those in the most need are treated first and taken to hospital.'
Transport for London said there was no service between Hammersmith and Edgware Road on the Circle and Hammersmith and City lines, while the police said the A40 was closed in both directions, owing to the fire.
London Fire Brigade said around 30 flats near the scene had been evacuated and a cordon was in place.
The East of England Ambulance Service has activated its Hazardous Area Response Team in case it is needed and was asked by London Ambulance Service to help with emergency calls around the outskirts of London. A spokeswoman said: 'Our thoughts are with all those involved – the public, local residents and all those responding to the incident, especially our friends and colleagues at London Ambulance Service.
'We were contacted in the early hours of the morning and were asked by LAS to provide mutual aid to emergency calls around our border areas with London.
'We have also activated our Hazardous Area response Team in case it is required to support this incident.'
The Metropolitan Police have set up a casualty bureau for anyone concerned about their friends and family on 0800 0961 233.
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