The Met is considering using rubber bullets against rioters in London this evening, as officers anticipate another night of "mass disorder".
The number of police on London's streets is set to nearly triple as the controversial new tactic is considered.
"That is one of the tactics that is available to us, and the people of London need to know that is a tactic we will use if it is deemed necessary," deputy assistant commissioner Stephen Kavanagh said.
"The Metropolitan police does not wish to use baton rounds but if it gets put in a position where it needs to protect people, we will do so."
Widespread use of rubber bullets appears unlikely. The fast-moving nature of marauding gangs means there is often not enough time for the bullets to reach areas where they could be used.
The Met is also mindful of fundamentally changing the nature of British policing through its actions. "We are not going to throw away 180 years of policing with communities lightly," DAC Kavanagh added.
"We had people as young as 11 being arrested for looting. Do we really want to see the police using these weapons against 11-year-olds?"
Cancelled leave, 12-hour shifts and reinforcements from at least 11 other police forces are swelling the Met's ranks above the 6,000 officers deployed on Monday night.
Not all will have riot shields, but vehicles are being borrowed from other police forces.
Every arrest means two officers are withdrawn from the street because they have to make statements, limiting the ability of the police to make instant arrests on the night.
The Met is seeking reinforcements of detectives from other police forces to help investigate the offences being committed.
"It will be very vigorous, it will be very thorough," Commander Simon Foy said of Operation Withern, the investigation into the disorder. "We will be remorseless in our pursuit of these individuals who have committed these offences."
The Met is meeting with community leaders every 24 hours to reassess the situation and has apologised for people having to "wake up and see buildings alight".
"London is - you know what, bloody resilient," DAC Kavanagh said.
"It will get through this. We will get through this."