Trapped families scream for help as they try to escape burning 24-storey London tower

Grenfell Tower in London on fire. (Photo: Courtesy)

A huge blaze has engulfed a 24-storey tower block in west London - with people trapped inside spotted screaming for help from windows and using knotted bedsheets to try to escape.

Shocking images show the fire tearing through Grenfell Tower in North Kensington as firefighters tackled the inferno - with around 120 flats affected.

Harrowing footage shows trapped residents hanging the makeshift ropes made of sheets and blankets out of their windows several storeys up as flames and debris rain down the side of the building.

A major incident has been declared and London Fire Brigade said 200 firefighters backed up by 40 engines were "working extremely hard" at the scene.

The fire has engulfed almost every floor from the 2nd to the 24th - and there are confused unconfirmed reports that there are still people trapped.

There are more than 20 ambulance crews at the scene and at least 30 people have been rushed to five hospitals across the capital - with many having managed to make it out in their pyjamas - but it's too early if there are any more unaccounted for.

An emergency number has been set up for people who are concerned for loved ones who live in the building - call the Casualty Bureau at 0800 0961 233.

The Metropolitan Police said earlier that residents were being evacuated and there were "a number of people being treated for a range of injuries."

One onlooker said he could hear people screaming, writing on Twitter: "More screams for help as the fire spreads to another side of the building."

Fabio Bebber, tweeting live from the scene, said "people are still trapped on their windows screaming for their lives saying they can't get out."

He added: "We can see how quick the fire spreads via the external panels.

"It's unbearable hearing someone screaming for their lives at Grenfell Tower"

One video captured residents trying to escape by using bedsheets tied together as a rope.

Another showed people flashing lights in their rooms to attract attention.

Another wrote: "Watching Grenfell Tower (24 storeys) burning in West London Latimer road area. All floors and columns burning."

George Clarke, the presenter of 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."

The fire is believed to have started around 1.16am - it’s unclear how it started.

Actor and writer Tim Downie, who lives around 600 metres from the scene in Latimer Road, said he feared the block could collapse.

He said: "It's horrendous. The whole building is engulfed in flames. It's gone. It's just a matter of time before this building collapses.

"It's the most terrifying thing I've ever seen. I just hope they have got everyone out.

"The first I knew was the noise of sirens, helicopters and shouting. I saw it engulfed in flames."

"People have been bringing water, clothes, anything they've got to help, out to the cordon.

"I have seen people coming out in their bedclothes - it's just very distressing."

Meanwhile it's emerged residents had issued a chilling warning about fire safety just months before this morning’s blaze.

In a series of blog posts since 2013, a residents’ group called the Grenfell Action Group repeatedly criticised Kensington and Chelsea Tenant Management Organisation (KCTMO) - the company which manages the tower block - over its fire safety record.

This morning Assistant Commissioner Dan Daly from the London Fire Brigade described the blaze as "large and very serious".

He said: "Firefighters wearing breathing apparatus are working extremely hard in very difficult conditions to tackle this fire.

"The Brigade was called to the fire at 12.54 and is still at the scene.

"Fire crews from North Kensington, Kensington, Hammersmith and Paddington and from surrounding fire stations are in attendance."

A Met Police spokesman said people were being treated at the scene for smoke inhalation.

They added: “Police were called at 1.16am on Wednesday, 14 June to reports of a large fire at a block of flats in the Lancaster West Estate, W11.

“Officers, the London Fire Brigade and the London Ambulance Service are currently at the scene. An evacuation process is underway.

“At this stage we are aware of two people being treated at the scene for smoke inhalation.

“Cordons are in place and it is advised that the estate and surrounding area is avoided.”

The Metropolitan Police have set up a casualty bureau for anyone concerned about their friends and family on 0800 0961 233.