A total of 528 knives were recovered as a result of 26,777 searches during Operation Blunt 2.

The blitz was launched by Metropolitan Police Commissioner Sir Ian Blair in response to a wave of killings, particularly among teenagers, in the capital. He unveiled the figures alongside London Mayor Boris Johnson at City Hall.

They came as three teenagers remained in custody after being arrested by detectives investigating the murder of 16-year-old Ben Kinsella.

Hundreds of people, including friends and relatives of the young student, took to the streets on Tuesday to demand an end to knife crime.

The new figures revealed that 1,214 people were arrested for possession of weapons and other knife-related crimes between May 19 and June 29.

Many were recovered during stop and search operations in high streets and at transport hubs, while others were found in weapons stashes.

Sir Ian said the stabbing of Ben in Islington at the weekend showed "the problem of knife crime is still with us".

Mr Johnson said Operation Blunt was only one area in which the authorities are working to make London safer.

He said: "Everybody is shocked by the level of violence we are seeing, particularly towards young people in London, and we must all work as hard as we can together to reverse this dreadful trend."