An elderly woman and her teenaged granddaughter were strangled to death allegedly by two of their relatives in their house at Nihal Vihar here on Friday over a monetary dispute.

Sixty-year-old Krishna Devi and her granddaughter Nancy (14) were strangled to death in their sleep allegedly by Dinesh and Vikas who had come to meet them on Thursday around 9-30 p.m.

The elderly woman's son Satpal, a shopkeeper, along with his wife Sonia was away to Kurukshetra in Haryana to meet their relatives for the settlement of the dispute with Dinesh when the incident took place.

“Satpal had lent Dinesh Rs.3.5 lakh a few months ago and was now asking him to return the money. It often led to altercation between the two. On Friday, Dinesh came to Satpal's house along with his relative Vikas and the two had an argument with Krishna Devi over the delay in returning the money. After the elderly woman went to sleep along with her grandchildren, Dinesh and Vikas strangled the woman and her teenaged granddaughter and escaped from the rear door,” said Deputy Commissioner of Police (West) V. Renganathan.

The double murder came to light when the elderly woman's minor grandchildren, Rishab and Isha, got up in the morning and found the two dead. The two then informed their relatives and parents. The matter was then reported to the police.

It is suspected that the accused offered tea laced with sedatives to the woman and her grandchildren and committed the murder after they fell unconscious. “We are waiting for the post-mortem report to ascertain whether the accused had rendered the victims unconscious before the murder or not,” said a senior police officer.