Pratiba and Kishore were married in November last year - almost exactly to the date.
A 23-year-old Karnataka woman - who had given birth less than two weeks ago - was allegedly murdered by her husband, a policeman, who suspected she was in a relationship with another man.
Three others have also been arrested in connection with the woman's death.
Police have said the husband, D Kishore, first consumed a poisonous substance - in an apparent bid to die by suicide - before he strangled his wife, Pratibha S. According to media reports, Pratibha was living at her parents' home in Hoskote Taluk, and gave birth to her baby - a boy - on October 28.
Kishore was living in the town of Chamarajanagar, which is around 230 km away.
The young woman's distraught father has branded his son-in-law a "psycho".
"We married our daughter to him... thinking he is a good man, but he turned out to be a criminal. We want justice. He needs to be punished. I do not want another girl to go through what my daughter did."
Pratibha, who had a degree in Computer Science, and 32-year-old Kishore, who is from Veerapura in Kolar district, were wed in November last year. Her father has also alleged dowry demands.
According to the police, Kishore and Pratibha had an acrimonious telephone exchange on Sunday evening - one that left the new mother in tears. Her mother told her to disconnect the call and suggested she not speak to Kishore for a while, for fear of upsetting the new-born child.
On Monday, when Pratibha checked her phone, she found 150 missed calls.
Later in the day Kishore reportedly landed up at his in-laws' home and cornered his wife inside a locked room, where he killed her. Pratibha's mother was on the roof at the time, police said.
According to The Times of India, Kishore confessed to his mother-in-law before escaping. "Kondu bitte avalna, kondu bitte (I killed her, I killed her)," he reportedly said.
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