Aligarh (UP), Sep 6 : A 55-year-old woman and her 22-year-old adopted daughter were allegedly beaten to death by her in-laws over a property dispute in Aligarh district, barely a week after her husband's death. The double murder took place at Kaimthal under the Gonda police limits when Mukesh Devi was attending her husband's 'terahvin' (ritual conducted on the 13th day of the mourning period) along with daughter Priyanka at her in-laws' place. Mukesh Devi's husband, Surender Singh, had died of a heart attack in Delhi on August 31. At the ritual, Mukesh Devi was attacked by her brother-in-law and others with a stick and heavy objects. When her daughter tried to save her, she was also brutally assaulted. Both suffered head injuries and were declared dead at a nearby hospital, police said. An FIR has been registered against seven accused -- Dharmveer Singh, Mona Singh, Dubla Singh, Ramesh Singh, Neeraj Singh, Sonu Singh and Rakesh Singh -- under IPC sections 302 (murder) and 147 (rioting) following a complaint by the woman's brother Bhola Singh. SP (Aligarh rural) Palash Bansal said, "Five police teams have been formed to arrest the accused. We are investigating the matter and action will be taken soon." Mukesh Devi's nephew Bablu added, "My aunt married Surender Singh of Kaimthal nearly 30 years ago. They later settled in Delhi. My uncle had recently retired from the Delhi Transport Corporation. He died a few days ago and his brother brought the body to his native place for cremation. On Monday, as we visited the house for the terahvin, there was a heated argument between my aunt and her brother-in-law over property. It soon turned ugly and the latter attacked her." "She was murdered for three bighas of land as the accused did not want the property to go to her adopted child. Her daughter was working at a private firm in Delhi," a neighbour said. /IANS