UK-Crime
Four men, including a teenager, have been stabbed to death in less than 24 hours in a spate of separate knife attacks in London.

A 19-year-old youth, who has not been named, became the 20th teenager to be killed in the British capital after suffering multiple stab wounds in Edmonton, north London on Thursday.

Later in the day, two men in their 20s were killed in attacks a few miles away in Leyton and Walthamstow, east London, while a 40- year old died from stab wounds after being found in Tottenham, north London.

London Mayor Boris Johnson expressed his deep regret at the latest spate of killings in Britain's growing problems of knife crimes.

"We need to do all we can to address the long term complex root causes of violence as well as ensuring the police are providing an effective deterrent to those who carry knives and guns. We are in this together and we all need to take responsibility," Johnson said.

Last month, Prime Minister Gordon Brown called for the age of teenager prosecutions for carrying a knife to be lowered at a summit with police chiefs to tackle fears that street violence was spiralling out of control.