A 36-year-old mother calmly called police to her suburban home on Wednesday morning, and greeted the stunned officers at the door with the words "I just killed my kids."
Ms Andrea Yates was breathing heavily and seemed panicked as she led an officer into the house and then to a bedroom. Police discovered five children dead in the house. The boys and a girl were discovered on a bed with a sheet covering them. They were identified as: Mary Yates, 6 months; Luke Yates, 2; Paul Yates, 3; and John Yates, 5.
A police spokesman said that seven-year-old Noah Yates was found in a bathtub. All of the children had been drowned. Ms Yates was arrested and charged with murder. Police had no explanation as to how she managed to systematically drown all five children.
Her husband, Mr Russell Yates, works for NASA on the space shuttle programme. After phoning the police, Ms Yates called him at work and reportedly said: "You better come home."
Ms Yates, a frail-looking woman who wears glasses, was being treated for postpartum depression for the past two years, her husband told police. She was so depressed over the weekend that she could not accompany her children to a party in the neighbourhood. Mr Yates told officers his wife was on medication. She had tried to commit suicide two years before with a prescription drug overdose.
Neighbours were stunned to learn of her admission to police that she had killed her children. The neighbour who hosted the party Ms Yates did not attend, Ms Pat Salas, told a local television station: "We asked him why she didn't come. He said she stayed [at home] because she was going through a bout of depression from having babies. That's what he said."
The children were being home schooled and were not registered at area schools.
Postpartum depression, which affects roughly 8 to 15 per cent of mothers, usually starts about four weeks after the birth of a child and lasts for months, according to experts. It can cause feelings of confusion, panic and hopelessness as well as changes in eating and sleeping patterns. It is usually mild and responds well to treatment, but in rare, severe cases it has led to violence.
In Houston, postpartum depression has been cited in a few recent cases of mothers killing their children. In 1998, a mother strangled her four-month-old son with rosary beads. Doctors' psychiatric evaluations diagnosing her as psychotic, partly because of postpartum depression, were introduced in her trial. She was found not guilty by reason of insanity.
A social agency, Child Protective Services, said almost 80 per cent of children who die at the hands of their parents are under the age of three. Most of the children die of neglect.
Most women who kill their children are younger than Ms Yates and generally start out their adulthood as teenage mothers.
"My wife, I'm supportive of her," Mr Yates stated at his press conference. He added that she was not the same person who killed the children.
"What happened was just incomprehensible. I've got really two tragedies . . . I've got my children and I've got my wife. I want her to recover," he said.
Relatives said Ms Yates was a registered nurse who graduated from the University of Houston. She had worked as a nurse but became a stay-at-home mother, home-schooling her children.