TRAGEDY: Many Feared Dead As Massive Flames Engulf 24-storey Grenfell Tower In London

LONDON — Deaths were confirmed early Wednesday after a blaze ripped through a high-rise apartment block in the British capital as residents slept. At least 50 people were injured, according to authorities.

More than 250 firefighters battled the inferno at Grenfell Tower through the night. Witnesses told of hearing people calling for help from within the building as flames quickly spread upwards.

Local resident Tim Downie told NBC News he saw "people dangling children out the windows to try and get them to safety."

London Fire Brigade Commissioner Dany Cotton called it an "unprecedented incident," adding that a "number of fatalities" had been confirmed.

"In my 29 years of being a firefighter, I have never, ever seen anything of this scale," Cotton said. "This is a major fire that’s affected all floors of the 24-story structure from the second floor upwards."
She highlighted that "very large numbers" were rescued by emergency crews from the building.

Local officials believe that several hundred people were in the building at the time. The high-rise had a "stay put" policy in the event of a fire — with residents urged to shut their windows and doors and await rescue.

Michael Paramasivan was wearing only underwear and a robe when he fled the seventh floor about 35 minutes after the blaze was reported.

"They say you're supposed to put a towel under the door and wait for rescue but I wasn't going to hang around," the 37-year-old told NBC News. "There was some kind of alarm but it was barely audible. It certainly wouldn't have woken you up."

Paramasivan described the scene in the stairwell as an "absolute horror story."

He added: "There was smoke everywhere, people screaming and shouting. It all happened so fast but was really, really frightening. I'm shaking."

Grenfell Tower dates to the 1970s and features around 130 units. It is located about a mile northwest of Kensington Palace and is also near the Portobello Road market tourist attraction.

Paul Littlejohn, 41, who lives nearby, added: "I've seen a few familiar faces this morning and I was very relieved to see them but many other people say there are missing people inside."

The London Fire Brigade sent 40 vehicles to the scene after being called at 12:54 a.m. Wednesday local time (7:54 p.m. ET Tuesday). At least 50 patients were later transported to five local hospitals.

At 8:30 a.m. local time (3:30 a.m. ET), black smoke was still pouring from every floor of the building.

Surrounding streets up to a mile away were covered in a layer of ash Wednesday morning as a police helicopter buzzed over the area — an ethnically and economically diverse part of west London.

Image: Media outside a huge tower block fire in West London
Smoke billows from the 24-story Grenfall Tower in London early Wednesday. Andy Rain / EPA
Ousama Itani, who lives nearby, told NBC News that one of his relatives heard people screaming from the building.

"We saw apartment after apartment getting lit up into flames," Itani added.

Nassima Boutrig, who lives opposite the tower, told The Associated Press that she heard people shouting: "Help, help, help."

She added: "The fire brigade could only help downstairs. It was fire up, up, up. They couldn't stop the fire."

Residents were hurrying along the streets trying to find news of neighbors or family members.

Kidan Opbekke, 39, was returning to her home in a nearby street after a night shift at work when she saw the aftermath of the blaze.

"A friend of mine, from Eritrea, she cannot find her daughter," she sobbed in the street. "She got out from the fire but she cannot find her daughter."

Opbekke added: "This is terrible. There is nothing we can do except pray. We just came here to pray. And why, why did this happen?"

At the nearby Latymer Community Church, some of the shocked survivors were being given water and food. A local mosque also opened its doors.

"We will be providing temporary shelter and food for anyone of any faith or no faith affected by the fire," said Abdurahman Sayed, the head of the Al Manaar Mosque.

Image: A resident in a nearby building watches smoke rise from a building on fire in London
A resident of a nearby building watches smoke rise from Grenfell Tower early on Wednesday. Matt Dunham / AP
Authorities said the cause of the blaze remained unclear early Wednesday.

A structural engineer was sent to the scene to monitor whether the high-rise remained stable.

A newsletter distributed by Grenfell Tower's managers in May 2016 advised that "you are generally safest to stay put in your home to begin with; the fire brigade will arrive very quickly if a fire is reported.”

It added that “smoke detection systems have been upgraded and extended" as part of a $12.8 million refurbishment project.

However, residents complained about fire safety standards in November — warning that only a serious blaze would make authorities listen.