Chandigarh, Sept. 20: A teenager and her boyfriend allegedly drugged and strangled seven members of her family, including children aged three to five, because the elders would not let the couple marry.

Sonam, 19, looked nonchalant as she faced the media today and coolly admitted her “mistake”.

“Galti ho gayi,” the undergraduate college student said.

She and boyfriend Naveen, who is doing a computer course, had been arrested yesterday after the September 14 murders in Kabulpur near Rohtak, Haryana,.

Officers said the family would not consent to the marriage because the girl and the boy belonged to the same gotra (clan or lineage).

“The family considered marriage within the same sub-caste a sin. So the duo planned to mix sedatives with their dinner and strangle them after they fell asleep,” Rohtak superintendent of police Anil Kumar Rao said.

The victims include Sonam’s parents Surender and Promilla, grandmother Bhooroo, brother Arvind and three cousins aged three to five: Vishal, Sonika and Monica. The head of the family, retired teacher Taqdir Singh, survived since he was sleeping outside, the police said.

After the murders, Sonam swallowed a few sedatives and fell asleep too, deputy superintendent of police Dalbir Singh, who is investigating the case, said.

The police said Sonam had called Naveen, who lived in the same village, on his mobile after everyone at her home had fallen asleep. The grandmother was strangled first, then the parents and the brother.

The children were killed probably because the couple feared they may have seen or heard something, officers said. Naveen then allegedly left the village to stay with another relative.

“He even took away some valuables to make it look like a dacoity,” Dalbir said.

“Initially, we suspected another son of Taqdir, but when Sonam kept changing her statements, suspicion fell on her.”