Police investigating the murder of a pensioner in her farm cottage have again appealed for private CCTV footage to be handed in.

Janet Methven, known to friends as Jenny, was found dead in her home by her son on Monday afternoon.

She died in the Kildinny Farm cottage they shared in Forteviot, Perthshire at about 5.15pm.

A murder inquiry was launched last night following the results of a post-mortem examination which revealed the 80-year-old had suffered multiple injuries on her head and body.

Detective Chief Inspector Colin Gall has issued a second appeal to householders and businesses in the Strathearn valley area to hand over any CCTV footage to help police build up a "full picture" of what could have happened.

Initial appeals for footage from private video surveillance systems have so far proved unsuccessful, he said.

Officers are continuing a forensic examination of Mrs Methven's property and have drafted in help from the National Policing Improvement Agency.

Police say they have found no sign of forced entry to the cottage or of any property being stolen. They say they keep "an open mind" about whether the death was linked to recent crimes in the area, including thefts and bogus callers.

It is believed a friend of Mrs Methven was the last person to speak to her, on the phone at about 10.30am on Monday.

Tayside Police say they hope someone saw her during the day on Monday and can help piece together her last known movements. Officers also want to hear from motorists or walkers who were in the area between Dunning and Bridge of Earn around Monday tea-time.

DCI Gall said: "We have appealed for residents and businesses to contact us if they have CCTV at home or their workplace, thus far without success. I cannot stress strongly enough that such footage could potentially be of great assistance to us.

"I am not restricting this appeal just to premises in Forteviot and neighbouring Forgandenny. We want to build as full a picture as possible of who was in the area during the day on Monday and to this end I would ask people in neighbouring areas out to Perth, Auchterarder and Glenfarg to get in touch if they have CCTV, Indeed, all areas extending out to and around the A9 and M90.

"Tell us if you have CCTV and we will come to you. Time is of the essence because some CCTV systems will re-record over previous footage.

"At the same time we would appeal to anyone who was in Forteviot and the surrounding area on Monday to contact us as they could have valuable information for us. That includes residents, people who work in the area and people who passed through, for example delivery workers or bus drivers."

Mrs Methven is said to have been well-liked and respected in her community and could often be seen walking her two-year-old spaniel.

Her son David Methven said his mother's death has "absolutely devastated" him.

Divisional Superintendent Jim Leslie said: "I feel that it is important to take this opportunity to reassure people that this sort of crime is extremely rare. There is no evidence whatsoever to suggest that there will be a repetition of it."