In a statement recorded before a Hisar magistrate, "My father wanted me to divorce my husband," she said.
Narrating the sequence of events on the day, she said she was returning from her in-laws house in Saharanpur to Litani with her husband Sanjiv. En route, they picked up her sister Priyanka from her school in Hisar.
But on the way, she had an altercation with Sanjiv who deserted them and left for Hisar, the 22-year-old said.
Later, Sonia said, her father was angry with her for bringing Priyanka from school on the fateful day.
She claimed to have 'killed her father and others, one by one with the help of an iron rod, in a fit of anger as the head of the family did not love her'.
After allegedly killing the others, she consumed poison to end her life and had to be admitted to a local hospital.
The bodies of Punia, his wife, daughter Priyanka, son Sunil, daughter-in-law and three grandchildren were found on the morning of August 24.
She has not yet been arrested, police sources said adding that she was being questioned regarding the murders.
Sonia was brought to Hisar after her discharge from the hospital at Barwala, they said.
Police parties have been sent to Faridabad to trace her husband.
They had already questioned Sanjiv's brother and now need Sanjiv's statement, they said.
The sources said they were still trying to ascertain if there were any other accomplices with Sonia in the farmhouse.
It was also strange that none of the servants or neighbours heard any noises when the family members were being killed, the sources added.
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