A Long Island woman described as emotionally disturbed and afraid of losing custody of her children called the police on Sunday and led officers into a blood-spattered bedroom where her young daughter and two small sons lay slain on a bed, investigators said.

The woman, Leatrice Brewer, 27, who lived with the children in an apartment in the Nassau County hamlet of New Cassel, was taken to a hospital for physical and mental examinations, the police said. Late Sunday evening, she was charged with the murder of all three children.

Neither the police nor the county medical examiner said what caused the death of the children, who were identified as Jewell Ward, 6; Michael Demesyeux, 5; and Innocent Demesyeux, 18 months old. But investigators said one appeared to have been drowned, while the others had been slashed to death.