A DANGEROUS criminal who carried out a "savage and senseless" attack on a lone female tourist who later died was jailed for life yesterday.

Sentencing Colin Ross to a minimum of 20 years, Lord Wheatley also imposed Scotland's first lifelong restriction order. It means that he will be under strict and constant supervision until he dies.

The judge said that, even after Ross has served his prison sentence, he should be considered for release only when the parole board was satisfied he was no longer a danger to the public.

Ross savagely battered a defenceless 57-year-old American primary school teacher with a metal pipe and a boulder as she walked alone on a secluded Highland path.

Marty Layman-Mendonca, from Vermont, was discovered bya police dog handler on a remote forestry track at Blackford, near Inverness. The attack left her in a coma. She was eventually flown back to the US where, two months later, in a hospital in Maine, she died.

Ross, 34, carried out the assault just six days after an order was granted banning him from approaching any woman. He had previously been arrested with what police believed to be a "rape kit" - a makeshift hood, a knife, gloves, electrical tape and condoms. The attack on Ms Layman-Mendonca took place less than a month after he was released - early - from a three-year sentence for an attack on a female German tourist.

At the High Court in Edinburgh, Lord Wheatley told Ross: "You have pled guilty to a dreadful crime, which involved a savage and senseless assault on a defenceless middle-aged woman."

He said that photographs of the injuries inflicted by Ross were among "the most horrifying" seen by the court.

"The violence was described as of an almost unimaginable kind. The victim was a 57year-old lady from Vermont who taught children with learning difficulties, " he said.

"From the information before me it is clear you knew exactly what you were doing. You had planned this attack with some care."

Ross, of Waterloo Place, Inverness, had earlier admitted attempting to murder Ms Layman-Mendonca on July 5 this year. After she was struck repeatedly with a metal pipe she was thrown unconscious into woodland and hit with a boulder. Ross then robbed her of cash, a rucksack and other valuables.

Days before the assault he had hidden clean clothes, a sponge and disinfectant near the scene. He engaged his victim in conversation before he "went into a frenzy" and repeatedly hit the slight-built woman on the head with his weapons. She suffered at least 19 blows which inflicted horrific injuries to her eye sockets, cheeks and jaw.

The victim's friends contacted police after she failed to return from her walk on the Great Glen Way. A police dog found her lying unconscious in a ditch with her wrists tied with shoelaces.

The teacher had believed Scotland to be the most welcoming place on earth.

In May 2004, Ross attacked a German tourist, 36-year-old Ina Bruns, near Cawdor Castle, outside Nairn.

His victim managed to fend him off after arming herself with a piece of wood. He was subsequently released from a three-year sentence for the attack on June 9 this year.

Released from jail on June 29 this year, the authorities were granted a court order banning him from approaching any woman.