According to prosecution, Ranganayaki was living in a house belong to her and her younger sister Dhanaselvi at Periyarnagar in the district.
Dhanaselvi, with an aim of grabbing the house from her sister, engaged four persons with the help of her fried Panjavarnam to murder Ranganayaki.
On June 2, 2014 when Ranganayaki was alone in the house Dhanaselvi and Panjavarnam and the four others strangulated her to death and took away Rs 1.10 lakh in cash and 13.5 sovereigns of gold jewellery from there.
Investigations revealed involvement of Dhanaselvi, Panjavarnam, Selvam, Mathivanan, Shankar and Balusamy in the murder. Police framed cases under various sections of IPC including 302 (murder), 120B (criminal conspiracy) and 379 (theft) and arrested them.
District Mahila Court Judge N Thirunavukkarasu awarded life sentence to all the six besides slapping a fine of Rs 50,000 on each of them yesterday.