A double-decker bus was commandeered by police to prevent a planned gang fight that would almost certainly have resulted in death, Scotland Yard said yesterday.

Officers in Deptford, South London, arrested 24 teenagers aged between 14 and 18 and seized six knives, a claw hammer, a metal bar, a mallet, two wrench handles, a metal baseball bat, two screwdrivers, a corkscrew and a golf club.

The incident took place on Saturday night, three miles from where Jimmy Mizen, 16, bled to death after being stabbed with broken glass a week before.

Boris Johnson, the Mayor of London, who has promised to draft in more police officers to work on the transport network, said that high-profile swoops would become increasingly common as the clampdown on knife crime in the capital continued.

A Metropolitan Police spokesman confirmed that the seizure of the weapons was part of Operation Blunt 2, which began last week to reduce knife crime. Senior officers said that they would carry out “in-your-face” policing to try to combat the rise in stabbings among young people.

So far this year 13 teenagers have been murdered in London, nine of whom were stabbed.

Officers patrolling in the Deptford area became suspicious when they observed the behaviour of a large group of youths waiting at a bus stop.

The patrol called for back-up, watched the teenagers as they boarded a No 47 bus - which runs between Catford and Shoreditch - and then followed it. When extra officers arrived the bus was stopped and a large number of officers got on board.

On seeing the police, most of the passengers on the lower deck got off. The doors were then locked and the bus was driven to Lewisham police station.

All the teenagers on the top deck were arrested on suspicion of conspiracy to commit violent disorder. They have been released on bail pending further questioning. Detective Inspector Tony Anderson, who is leading the inquiry, appealed for passengers who were on the bus when police took it over to come forward. “They may have valuable information,” he said.

Mr Anderson took the unusual step of giving a mobile phone number - 07788 916864 - on which witnesses could contact his team.

Mr Johnson said that he was shocked by the level of violence on London’s streets and promised an effective response.

The Mayor said: “This action by the police will become more and more common as we work together in the vital fightback against the scourge of violent crime that is ruining young lives and devastating families across the capital.

“We will be doing all we can to get to grips with crime - increasing intelligence-led police initiatives focused on key estates, funding more hand-held scanners and knife arches to detect guns and knives, and leading a huge drive to get kids off the streets and into activities which raise their aspirations and help turn their lives around.”

Times Recommends

• Feeble wind farms fail to hit full power
• Students revolt as 150 are crammed into one tutorial
• Politics is off as Mumsnetters get raunchy