Four siblings who were killed in a fire at their home died of smoke inhalation, post-mortem examinations have established.
Reece Smith, 19, four-year-old twins Holly and Ella and Jordan, two, died after a blaze broke out at their converted bungalow in Lytham Road, Freckleton, Lancashire, on Saturday.
The four victims were taken to Preston Royal Infirmary but were later pronounced dead.
Their mother Michelle Smith, 36, who has five other children, was led out of the house by firefighters and was not thought to be injured. The blaze took hold hours after the family held a party at the house to celebrate her birthday.
A spokeswoman for Lancashire Police said post-mortems were carried out by a Home Office pathologist earlier today and each victim died as a result of the effects of inhaling smoke. She added that a joint police and fire service investigation into the cause was continuing.
According to reports, a distraught Ms Smith said: "I have lost the lights of my life ... where can I turn?"
Her father, Keith Smith, 56, said his daughter was staying with relatives in the area.
Mr Smith, who found out about the blaze on the news, said: "It's very shocking, these are such tragic circumstances."
Lancashire Fire and Rescue Service was called to the scene at about 11.20pm on Saturday. Six firefighters wearing breathing apparatus rescued the four casualties while another person who did not need medical attention was led out.
Sources said that a birthday party took place at the house and it appeared those who got out safely were downstairs when the fire broke out.