Officers were called by the ambulance service at around 11:40 a.m. on July 9 and found the 78-year-old deceased inside the property with serious injuries.
Police said enquiries are moving quickly for a suspect believed to be a white male, while detectives carry out house-to-house and CCTV checks.
A cordon and road closures remain in place around the home as specialist officers continue forensic examinations and maintain a significant police presence.