Anti-terrorism police patrols will be introduced across London to crackdown on terrorism activity and other crimes of "hostile reconnaissance".
The deployment, due to launch in for all boroughs over the coming months, began in Wandsworth and Lambeth on Monday (November 28).
Scotland Yard stressed the move was "not in response to a specific threat", but said it is based on "extensive research into the psychology of criminals and what undermines their activities".
The dog and boats units will also be at hand, supported by the territorial support unit riot police.
Deputy Mayor for policing and crime, Sophie Linden, said: "We know our emergency services do a great job every single day protecting our city.
"However we cannot be complacent, which is why it is good to see the Met rolling out Project Servator to help deter and detect crime in our city’s busiest areas.
"This tactic was endorsed by Lord Harris in his review of London’s preparedness for a terror attack, commissioned by the mayor."
The patrols have begun a mere few weeks after it was announced by British Transport Police that armed officers will travel on the tubes in between their jobs to "provide reassurance and respond to whatever threat there may be".
Extra police were stationed at London tube network entrances after a officers were called to a bomb scare on the Jubilee Line in October.
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The Metropolitan Police told getwestlondon that commuters can "expect to see more officers, including armed police in and around the transport hubs".
The Joint Terrorism Analysis Centre raised the threat level for London transport to "severe" last month , meaning "an attack is likely" and police have urged commuters to be vigilant and report anything they feel is suspicious.
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