Martin Dinnegan, 14, was knifed to death in Islington, north London, after he and his friends became involved in an argument with a group of up to 20 youths.

His mother, Lorraine Dinnegan, said her "lovely" son did not deserve her die and called for action to be taken to combat the scourge of knife crime.

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

Just hours after Martin was killed, the capital's spate of fatal knife attacks claimed another young victim when an 18-year-old man was stabbed in a separate incident.

Abu Shahin, of Manor Park, east London, died in hospital after being attacked in the street in Ilford, east London, by two suspects.

A 20-year-old man was arrested in connection with the death and is currently being held at an east London police station.

Police condemned the "vicious" stabbing of 14-year-old Martin and said they were keeping an open mind about the motive for the attack.

Sadik Turan, 21, a friend of the teenager, said he had been told Martin was killed for "looking" at another gang of youths.

Angela Fitzgerald, 53, a friend of the Dinnegan family, said the schoolboy was with two 17-year-old boys shortly before he was stabbed.