A man who stabbed a youth after being tormented by rowdy teenagers in the area where he lived was yesterday jailed for three years.

Derek Manson, 53, claimed he and other residents had been long-suffering victims of antisocial behaviour by teenage gangs.

He snapped last June when, after being verbally abused by a mob, he caught a boy urinating next to his home in Hyndland, in Glasgow's west end.

Manson, described as semi-retired, went out armed with a kitchen knife and stabbed one of the youths who had attacked him moments earlier.

Glasgow Sheriff Court heard Manson surrendered himself to police soon after the attack telling them: "I am the man that you are looking for." He also said it had been "a moment of madness". He admitted assaulting Darren Foy, 16, to his severe injury, permanent disfigurement and to the danger of his life when he appeared in court last month.

Sentencing Manson yesterday at Glasgow Sheriff Court Sheriff Robert Anthony, QC, said that despite the trouble he suffered, custody was appropriate as he had taken "matters into his own hands".

A Tory MSP last night echoed the Sheriff's sentiments but said the case underlined the frustration of law-abiding citizens who felt their complaints were not dealt with and acted upon by the relevant authorities.

The court heard that Mr Foy and a number of other boys had been walking in Hyndland on June 16 last year after an alcohol-fuelled party at a friend's home.

One of the group stopped and then urinated at an archway near to Manson's flat in Novar Drive. While the rest of the mob waited for him, Manson opened his window and yelled at them to go away.

The youths shouted at him to "f*** off" and "go back to bed". Manson then left his flat armed with a kitchen knife and followed the group into nearby Hyndland Road.

Manson then confronted Mr Foy.

Imran Bashir, prosecuting, told the court: "There was jostling between both of them. During this, the complainer pushed the accused, who fell to the ground.

"When he fell, Darren Foy kicked him and immediately Manson got up, lunged towards him striking him with the knife on the left side of the abdomen."

The teenager slumped to the ground with the knife still protruding from his stomach as Manson ran off.

Mr Foy spent two-and-a half weeks in hospital as a result and suffered blood poisoning.

Matthew Harding, for the defence, said Manson had consulted community police about trouble in the area. There had been a crackdown, but this was not sustained, and at the time of the stabbing matters had deteriorated.

Mr Harding said his client considered calling police on the night of the stabbing but decided not to because he feared it would be treated as "a low-level incident".

Sheriff Anthony said Manson would have been sentenced to four years in prison if he had not pled guilty.

He added: "You went out armed with a lethal weapon. There is a problem in Glasgow and Scotland as a whole with the use of weapons.

"Steps must be taken to address this. A message has to go out that those who are prepared to go out armed and assault others must be dealt with appropriately."

Reacting to the sentence yesterday, Bill Aitken, the Tory justice spokesman and convener of the Justice Committee in the Scottish Parliament, said "There is no justification for taking the law into one's own hands.

"But this is yet another case underlining the frustration that law-abiding citizens feel when their complaints are not dealt with and acted upon."