Mabel Leyshon was repeatedly stabbed

Police want to trace the driver of a light-coloured - possibly blue - van, seen parked in Ms Leyshon's driveway in the days before her death.

Despite repeated appeals, the owner of the van has not come forward.

Police will now be examining footage of traffic crossing the Britannia Bridge for clues as part of the intense investigation to locate the driver, even if it to eliminate him from the inquiry.

"We want the person who did this arrested as soon as possible and everything, and I emphasise everything, possible is being done," said Chief Superintendent Keith Humphreys

"We can't be satisfied until this person is arrested and facing prosecution," he said.

Detectives have already enlisted the help of the national crime faculty and a criminal psychologist to create a profile of Ms Leyshon's attacker.

Forensic experts have been conducting a painstaking search for clues in the living room of a bungalow in Llanfairpwll.

Chief Superintendent Keith Humphreys

Meanwhile, officers continue to search for the murder weapon, which they describe as "some kind of bladed weapon".

Details of a salesman seen in Llanfairpwll on Friday were also released.

DCI Clayton said officers had been stunned by the ferocity of the attack, which he described as "callous and brutal".

It has emerged that Mrs Leyshon had spoken to a friend from Birkenhead, Liverpool, on the telephone on Saturday at 1430GMT.

But what happened between that point and when she was found on Sunday remains a mystery.

Mrs Leyshon had lived in Lon Pant for 40 years and neighbours said she was a private but active and independent woman.

Persons with information should contact North Wales Police on 01286 684868.