Police investigating the death of Lancashire toddler Sophie Jones are examining the possibility that she died after drinking the heroin substitute Methadone.
The two-year-old was taken to hospital from an address in Jameson Street at about 11.45pm on Tuesday night after she reportedly suffered a cardiac arrest. She later died at Blackpool Victoria Hospital.
A post-mortem examination has so far failed to ascertain the cause of death and toxicology tests have been ordered. Police said today detectives were investigating whether a substance, possibly Methadone, was removed from the house before paramedics arrived.
A 29-year-old woman and a 41-year-old man are being questioned on suspicion of manslaughter and attempting to pervert the course of justice. A 65-year-old woman and a 60-year-old man were also arrested but later released.
Detective Superintendent Paul Withers, of Lancashire Police, said: "This is a tragic incident where a little girl has lost her life.
"A full investigation is under way to try to establish exactly what has happened. Specially trained officers are offering support to the family."