Bloomberg wants to ramp up the security camera network in New York City's subways to mimic that in London's underground train system. London authorities say the city's train stations are watched by more than 12,000 cameras, and in a few years they aim to install a few thousand more. The additions would mean most people would be recorded when entering a subway system.
New York City has far fewer such cameras about 4,000 along its subways and Bloomberg has complained that half of them don't work. Police, instead, have had to rely on regular patrols.
"Crime rates in both the subway systems in London and New York City are as low as you can get, but there's always the threat of terrorism. ... Wouldn't you want to be safe?" Bloomberg told reporters. "I am here to learn from others, see what works best, and try to fix things before they become a problem."
London has one of the world's highest concentrations of surveillance cameras with a ring of them encircling the central business district. The so-called "ring of steel" was the inspiration for a 3,000-camera network being installed in lower Manhattan and midtown New York.
The New York Police Department hopes to install the 3,000 cameras by the end of 2011. It is also using private surveillance installed in major buildings as part of a massive security initiative.
Like New York, Britain's capital has been beefing up its counter-terrorist measures since a series of bomb attacks. More than 50 people were killed and hundreds were injured when four suicide bombers attacked London's subway system and a double-decker bus on July 7, 2005.
To years later, two car bombs were discovered in central London's entertainment district. The incident bore striking similarities to the failed Times Square bombing in New York earlier this month, when a 30-year-old Pakistani American tried to detonate a car bomb.
British terrorism minister Alan West has led talks with local authorities, emergency services and companies, which run major shopping malls or sports grounds aimed at lowering the risk from terrorism.
Mall security managers have been put on high alert for car bombs, and briefed to make regular 20-minute checks on delivery vehicles or other vans entering zones closed to the public. Security officials have also recommended linking camera systems to automatic number plate recognition software, hoping to flag up suspicious traffic.
An estimated 4 million closed circuit television cameras operate in Britain, and some civil liberties campaigners have warned the country is becoming a surveillance state.
London Mayor Boris Johnson said the cameras have been instrumental in driving crime down and piecing together key intelligence pieces.