Two more fatal stabbings in London have taken this year's grim toll past 50 but Scotland Yard said on Friday the city is not suffering an epidemic of knife crime.

A 20-year-old died from stab wounds on Thursday afternoon in Leyton, east London, and a man in his 20s was killed in Walthamstow later in the evening.

Up to July 7, 49 people had died from stab wounds in London this year. Police were unable to provide comparative figures for last year, though between April 2007 and March 2008 there were 160 homicides, 70 of which were stabbings.

The Metropolitan police have said tackling knife crime has overtaken terrorism as their number one priority. They have set up a 75-strong team to target those carrying weapons.

But speaking after the latest killings, a spokesman said: "I wouldn't describe it as an epidemic."

"There is an issue with knives and that is why we have launched Operation Blunt 2," he added, referring to a Met crackdown on knives.

Officers have searched 27,000 people, arrested more than 1,200 and seized 500 knives in London during the six-week campaign.

Four people have been arrested over the Leyton death. No one has yet been detained over the killing in Walthamstow.