A jilted man who tried to kill his ex-girlfriend after he discovered she had signed up for an online dating agency has been jailed for 13 years.

Simon Liddell had sneaked into Angela Rueter-Bell's Folkestone home and saw red when he found she was looking for a new love. He left with a pair of her knickers.

Having previously stalked the victim, the 49-year-old alcoholic then confronted her in the street and launched his knife attack.

Miss Rueter-Bell, 48, bravely attempted to fight him off and she was saved from serious injury by horrified witnesses who intervened.

Describing Liddell as "crazed" and finding him a danger, a judge imposed an extended sentence of 13 years in prison and two years extended licence.

He will not be released until the parole board decides it is safe to do so.

Liddell, of Clifton Road, Folkestone, admitted attempted murder.

Maidstone Crown Court heard he had known the teaching assistant for two years through mutual friends but they did not have a more serious relationship until about four months before the attack on November 9 last year.

At first, all was well. But it was while they went away together in September that Miss Rueter-Bell began to feel uneasy about Liddell's drinking. When they returned home she ended the relationship.

Prosecutor Danny Moore said they stayed in contact but on November 7 Liddell appeared from nowhere in Bouverie Road West and demanded to know why she had dumped him.

She told him it did not feel right and she did not have to explain herself to him. He then threatened: "I will kill you." She told him not to talk rubbish.

Miss Rueter-Bell later saw him outside her home when he told her he knew she was on a dating website. She checked it and saw that he had added his profile.

"The reason he knew about that was because he had broken into her house," said Mr Moore.

Police later found a piece of paper with the name of the website on it at Liddell's home, along with a pair of her knickers.

"I admit it. I tried to kill her. She went on a dating website. I had to do it..." - what Simon Liddell told police

On November 8, he hid behind a tree and when he saw her walking her dog again told her he would kill her. She told him to sober up.

The next day - her daughter's 16th birthday - she was pushing her bike up a steep hill in the Old High Street when Liddell appeared with a crazed look in his eyes and pulled a large kitchen knife from under his coat.

He raised the weapon above his head and stabbed at her chest. She blocked it with her hand and he then tried to knife her in the stomach. She turned away and he stabbed at her back.

"She was fighting all the time with him," said Mr Moore. "He said again: 'I will you.'"

One man saw the struggle in a doorway and struck Liddell on the side of the head with a drill he was holding. Retired company director Carl Hall managed to grab the knife and put him in an arm lock.

Miss Rueter-Bell was taken to hospital with serious defensive wounds to her hands.

Liddell told police: "I admit it. I tried to kill her. She went on a dating website. I had to do it."