CHENNAI: A 74-year-old woman succumbed to the injuries she sustained after her mentally unstable son attacked her with a wooden log at their home in Otteri last week. The police have altered the case from attempted murder to murder and arrested the accused.

Khatijabee (74) of Otteri had been living with her family since her husband Abdul Majeed died of illness four decades ago. She is survived by three children, Nazni Begum, Abdul Hafiz, and Imtiyaz.

Police said Imtiyaz (31), the youngest son, is mentally unstable.

On May 14, Khatijabee was alone at home when Imtiyaz allegedly struck her repeatedly on the head with a wooden log. Neighbours who heard her cries rushed in, rescued her, and admitted her to Government Kilpauk Medical College Hospital.

The Otteri police initially registered an attempted murder case and began an inquiry. After several days of treatment, her other son, Abdul Hafiz, shifted her to a private hospital on Wednesday night for advanced care, where she succumbed.

The police altered the case to murder and arrested Imtiyaz. He was produced before a magistrate and remanded in judicial custody.