Four children have died in a house fire which also left a toddler and two adults – who leapt to safety from a first-floor window – injured.
Neighbours reported hearing screams as the blaze, in the Highfields area of Stafford, took hold overnight.
The children killed in the fire were aged between three and eight, Staffordshire Police said.
Both adults, along with the toddler, are in hospital, but their injuries are not life-threatening.
The force named the four children, who have not been formally identified, as Riley Holt, aged eight, Keegan Unitt, aged six, Tilly Rose Unitt, aged four, and Olly Unitt, aged three.
Their two-year-old brother Jack survived, along with mother Natalie Unitt, 24. Her partner Chris Moulton, 28, also survived.
Tearful neighbours said they heard “screaming” and saw flames “lashing” out the windows.
Rob Barber, deputy chief fire officer for Staffordshire fire and rescue service could not comment on the cause and said the man, woman and toddler escaped the property before their arrival.
He added: “Our firefighters were faced with very difficult conditions inside the property due to the severity of the fire.”
Part of the roof has collapsed, windows were shattered and the rooms were left blackened by the blaze, which happened at about 02:40 GMT at the house on Sycamore Lane.
Staffordshire Police said Tilly was aged four and the three boys were aged three, six and eight.
‘Very hard to accept’
Nicola Glover, head teacher of Castlechurch Primary School, which Riley, Tilly and Olly attended, said the school was “absolutely devastated”.
“Riley was a very confident, excitable member of school who came everyday full of enthusiasm,” she said.
“He was a caring friend who hated to see anyone hurt or upset and would do his best to help or cheer them up.
“Riley had a great sense of humour and an infectious giggle. He was a very bright and articulate boy who showed interest in all areas and was always keen to ask lots of questions.
“Tilly was a happy little girl who loved coming to nursery. She was a friendly and caring child who loved to read stories, dress up and paint.
“Olly was a happy, loving boy who loved cuddles. He was always happy to come to nursery and loved to be in the role play area with the dolls.”
Kim Ellis, Head teacher at Marshlands School, where Keegan was a pupil, said he was “full of fun and mischief”.
“He loved school and everyone who worked with him loved him. It is very hard to accept what has happened.”
Neighbour Wendy Pickering was in tears as she remembered the children, who she often saw while taking her granddaughter to school.
“It is a real shock,” she said.
“We heard screaming, but we weren’t sure if the children were in the garden.”
Her husband Bryan said he was alerted to the fire by his dog barking during the night.
“The flames were lashing out of the upstairs window,” he said.
A hand-written note attached to a cuddly toy in an area nearby where people had laid down tributes read: “RIP Babes xx life is so so cruel. All our thoughts are with the family at this very sad time.”
Another note read: “Will be dearly missed, love Uncle Dave and Auntie Lou Lou”, while another added: “To my lovely grandkids I will always miss you. Love you always xxx.”
Chief Insp John Owen, of Staffordshire Police, described the blaze as “absolutely heartbreaking”.
At the scene
Sophie Madden, BBC News
Sycamore Lane is a quiet cul-de-sac nestled on the outskirts of Stafford.
But today it is filled with fire engines, police cars and emergency service personnel dealing with the wreckage of a burnt-out house ravaged by a fire which claimed the lives of four children.
A cordon, where journalists have gathered, blocks entry to the road. The mood is sombre as people try to go about their daily business.
Residents from neighbouring streets stop and ask police officers what has happened. Visibly shocked and upset, many become tearful as the full horror of the events became clear.
A West Midlands Ambulance Service spokeswoman said: “Tragically, four children from the property were confirmed dead on scene.
“Our thoughts are with the family at this exceptionally difficult time.”
Matthew Ellis, Staffordshire Commissioner for Police Fire and Crime, paid tribute to emergency services for working in “tragic and difficult circumstances in the middle of the night”.
“For something like this to happen it’s just heart-breaking,” he said.
“It’s very difficult to imagine just how professional and how dedicated these people are, but they are all human beings.”
Jeremy Lefroy, the Conservative MP for Stafford, described the fire as “unbelievably tragic”.
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