A bright, popular, teenager was stabbed to death by a gang of youths last night because they thought he had looked at them "the wrong way," his mother said today.

Demanding that police increase patrols to stop thuggish groups threatening innocent people, Lorraine Dinnegan said her son Martin was "a lovely boy" who did well at school, and had been murdered for no reason.

"How easy is it to stick a knife in someone? To take their life?" she asked reporters, standing at the site in Islington, north London, where her 14-year-old son was stabbed.

"Why is it happening, why is it still happening? How many more victims is there going to be? I’m lost for words.

"The police can do more. They need to be out more in local areas to deter clumps of teenagers hanging around together."

Describing the moment she and her family found out that her son had been stabbed, she said her eldest son received a phonecall at about 8.30pm yesterday.

"One of Martin’s friends phoned my eldest son to say Martin had been stabbed and they didn’t think he was breathing," she said.

"I’ve just been speaking to one of his friends - apparently they were looking at each other the wrong way."

Adding that she had "got this terrible numb feeling," she added: “I think I’m in shock at the moment. I just hope the police can catch them.

“He’s a lovely boy, he doesn’t deserve this, nobody deserves this, it’s horrible. He was a very popular boy, he was well-known and did very well in school.”

Angela Fitzgerald, a friend of the Dinnegan family, said Martin had been with 17-year-old friends just before he was attacked. They were returning to see him a few minutes later and saw him being assaulted.

She said they desperately tried to save him as he watched him going blue, with his eyes "just staring".

"They saw a row going on and saw Martin fall to the ground," she said. "He was lying on his back, they tried to call to him. He was very white and then started to go blue and his eyes were just staring.

"He gasped and they tried to get him up, then they saw blood all over his back. They tried to save him."

Mrs Fitzgerald, 53, said there was a lot of crime in the area and told how Martin had been assaulted in nearby Holloway Road in an incident about two months ago in which another boy was stabbed.

She said: "The boys Martin hung around with were good lads, they didn’t carry knives.

"There’s a lot of crime in the area. I get very worried about the boys around here. The assault in Holloway Road only happened very recently and there have been other incidents. I don’t think the police are doing enough to stop crime in the area."

Martin Dinnegan's stabbing was the latest in a wave of knife attacks blighting the capital. Since the beginning of the year, a dozen teenagers have been fatally stabbed or shot in the city, including the 14-year-old.

The latest killing will heighten calls for a curfew on teenagers, a move that police chiefs in the capital are thought to be considering.

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