A man killed his wife and three children, including a two-month-old girl, and left a note before he fled from their home in south Delhi's Mehrauli, the police said today. He was arrested later.
The accused, Upendra Shukla, is a private tutor. According to police, Mr Shukla wrote in the note that he killed his family but gave no reason why he did it.
The police said Mr Shukla slit the throats of his family around 2 am on Saturday; the knife has been found.
Neighbours found the bodies of his wife and the two other children - a seven-year-old girl and a five-year-old boy - after they broke open the door of the house with the help of the police.
The accused's mother-in-law grew suspicious when their room's door was found locked and on seeing him leave the house early morning. She then ran to their neighbours, who called the police control room.
The police said Mr Shukla had been suffering from depression.
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