Two stepbrothers, aged one and five, were believed to have been murdered by their Indonesian maid, who later committed suicide.
Their bodies were found sprawled in a pool of blood at their home in Sungai Buloh, Selangor, on Tuesday evening.
The boys were identified as Melvin Selvam Joseph and Koay Jia Hong, Malaysia's The Star reported.
It is learnt that the parents, a coffee shop operator and his wife, returned home at about 7pm to find the three of them with their throats slit.
Sungai Buloh Superintendent of Police Junaidi Bujang said initial investigations revealed that the maid, in her 30s, had slit the throat of the five-year-old upstairs before killing the one-year-old boy in the same manner on the ground floor near the kitchen.
Superintendent Junaidi said that the maid then slit her own throat.
He said three knives were found beside the maid, known only as Agnes, the New Straits Times reported.
A neighbour, Mr S. Sivakumar, 34, told The Star that no one else was at the home at the time of the incident.
He said: "The family usually goes out in the morning to operate their restaurant nearby, leaving the maid and the two boys at home."
He added there were nine people living in the house.
FOUL PLAY RULED OUT
The police have ruled out foul play as four Rottweilers owned by the family were guarding the house at the time of the incident.
Meanwhile, the maid is believed to be an illegal immigrant.
Indonesian Embassy consular affairs counsellor Dino Nurwahyudin said that the woman had no travel documents and her identity is still a mystery.
"We do not know who she is or how she entered the country as there are no documents or papers with her or her employers," The Star quoted the embassy official as saying.
Mr Dino said the embassy is working with the police both in Malaysia and Indonesia to ascertain her identity and hope to find her family.
The Indonesian Police attaché in the embassy, Mr Aby Nursetyanto, said the Malaysian police told them that Ms Agnes was introduced to the victims' family by a friend.
He said: "This friend had previously worked as the family's maid, before she had to quit to join her husband who works in Johor."
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