A teenager and three young children have died following a blaze at a house from which their mother was rescued.
Michelle Smith, who had celebrated her 36th birthday on Saturday and has five other children, was led out of the property by firefighters and is not thought to be hurt.
The victims have been named by their grandfather as Reece Smith, 19, four-year-old twins Holly and Ella Smith and two-year-old Jordan Smith.
It is understood the four were rescued from the property in Freckleton, Lancashire, and then taken to Preston Royal Infirmary, but medics were unable to save their lives after the fire late on Saturday night.
Police at the scene of the house fire in Freckleton, Lancashire
A police spokesman said there were other people also in the house at the time of the incident, and he would not comment on whether a party was held at the address in the evening.
Ms Smith’s father, Keith, 56, said his daughter was staying with relatives in the area.
House fire victims: (Top) Ella and Holly Smith, (bottom left) Jordan Smith, (bottom right) Reece Smith
Arriving at the scene, he said: “I found out about it on the news and heard there had been a fire at a house in Lytham Road and I started to think it might be Michelle and the kids.
“It’s very shocking, these are such tragic circumstances.
“I don’t know anything about what happened last night. They have lived here for about two and a half years – this was their grandmother’s former home.
“I haven’t had chance to speak to Michelle yet. It is just terrible. I last saw them all just after Christmas.
“I can’t think of any reason why this has happened. It has just come as a big shock.”
It is just terrible. I last saw them all just after Christmas. It has just come as a big shock.
Kevin Smith, father of Michelle Smith
A neighbour, who did not wish to be named, said Ms Smith had been living at the address since last summer.
The property, owned by Ms Smith’s late grandmother, had been vacant for some time while a loft extension was built, the neighbour added.
A joint police and fire investigation is under way after the blaze.
Phil Cox, group manager for Lancashire Fire and Rescue Service, said they were called to the house at 11.21pm.
As crews were heading to the property, they received calls saying people were trapped inside the property, including a number of small children.”As soon as the crews arrived it seemed quite a chaotic scene with a lot of people outside quite distressed,” he said.
“We sent in six firefighters who rescued four people and also led out one other person.
“We had police officers, fire officers and paramedics at the scene working on resuscitating the people brought out before they were taken to hospital.
“We would like to pass on our condolences to the family.
“There was a reasonable amount of smoke at the time, we were faced with quite a heavy smoke-logged building.”
A spokeswoman for the service said firefighters used six breathing apparatus, one lighting unit and two hose reels as they tried to tackle the blaze.
She added that there was “50% fire damage to a wardrobe and 100% smoke damage to the upstairs of the property”.
Sources said the cause of the blaze was not thought to be suspicious but investigations were ongoing.
Detective Andy Murphy, of Lancashire Constabulary, said: “We are trying to establish the cause of this fire. We are keeping an open mind at this stage as to what happened.”