Scotland Yard says it has smashed a drugs gang believed to be the biggest to target Britain. Raids were carried out on Tuesday morning on 17 London addresses and up to 25 in Colombia, in a co-ordinated international operation.
Raids 'smash drugs cartel'
Officers believe they have crushed the "top tier" of a Colombian-based cartel which other law enforcement agencies have been unable to penetrate.
The group is thought to be responsible for much of the drugs confiscated by the Met this year and detectives said it had "netted" over �100m in the past 18 months.
Colombia arrestsMost of the 12 people arrested in London on Tuesday were foreign nationals from South America, although some had permanent leave to remain in the UK. Another 15 were arrested in Colombia.
A bag containing �250,000 cash was found at one London address and Colombian authorities report confiscating a "large amount" of money.
Scotland Yard says it is the first time they have worked in close partnership with Colombian authorities.
They added the operation was expected to have a "massive impact" on the price and availability of cocaine in the UK.
The raids follow an 18-month investigation by Scotland Yard's covert Special Projects Unit during which time �20m of cocaine has been seized.
About 20 "minor players" were arrested during the course of the investigation on suspicion of drugs and money laundering offences.
But police were going after suspected "main players" in Tuesday's raids on homes and businesses, including a money exchange and a Colombian cafe.
Detective Chief Superintendent Sharon Kerr, head of the Flying Squad, said: "This is the first time in the history of policing we have been able to take out an entire network of individuals who have been peddling drugs and importing drugs from several continents."
She added: "This was the final stage of an operation against an enduring, sophisticated and hard-to-penetrate criminal network."
The existence of the Special Projects Unit, which tracks major drugs and firearms traffickers, as well as hitmen, was only confirmed by Scotland Yard last week to reassure the public police were winning the war on gun crime.
Special Projects head, Detective Chief Inspector Martin Molloy said he thought the raids would be "extremely significant" and a warning not to bring cocaine into the UK.
He added the scale of the network was illustrated by the fact that two gang members had laundered �17m through one business in 12 months.
None of the officers involved in the raids, which were mostly in Holloway, north London, in east London and in Brixton, south London, were armed.
Police said they were unlikely to meet resistance from suspects.
A battering ram was used by officers trying to gain access to one home in Canning Town, east London.
Metropolitan Police Commissioner Sir John Stevens said the operation was a huge success for the force and a "serious blow" to organised crime.
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