A man suspected of heading a vast international drugs, guns and money laundering empire was arrested during raids in the West Midlands, Ireland and mainland Europe.
Christy Kinahan, dubbed the "Irish Godfather", was held with his two sons when dozens of armed police descended on their six million euro (£5.2 million) mansion in Malaga, Spain.
The 53-year-old Irish-born British passport holder is alleged to be the kingpin of a global crime conspiracy which traded in drugs, guns and laundered hundreds of millions of euros in dirty cash.
About 230 officers have arrested nine men and two women as they searched business and residential premises in London, the Thames Valley, Kent and the West Midlands.
Those arrested in Britain included a 40-year-old woman from Sutton Coldfield; a 42-year-old man from Tamworth, a 42-year-old man from Datchet, Slough; a 69-year-old man from Westerham, Kent; a 38-year-old man from Headlington, Oxford; a 29-year-old woman from Sonning Common, Reading; a 43-year-old man from Canterbury, Kent; a 34-year-old man from Perivale Greenford and a 42-year-old man from Wandsworth Common, London. Two other men were arrested at premises in Middlesex and London.
More than 750 police officers were involved in the raids co-ordinated by police in London, Dublin and Malaga. Officers also searched properties in Belgium, Cyprus and Brazil.
The raids follow two years of preparation, including surveillance and monitoring of the gang's finances, and it is believed the case may develop into a massive fraud inquiry linked to the money laundering.
Kinahan, who has links to London, Dublin and the West Midlands, last surfaced in May 2008 when he was arrested by the Belgian federal police force for money laundering.
Wanted in several European states as well as UK Revenue and Customs over suspected money laundering, he has lived in mainland Europe since 2003, frustrating efforts to put him on trial.
Investigators have linked him to gangs of Turkish drug dealers specialising in heroin, cannabis growers in Morocco and ecstasy and amphetamine drug laboratories in Holland.
UK officials said European authorities had dealt a major blow to a prolific gangland operation, considered to be the number one crime gang operating out of Spain.
Trevor Pearce, executive director of the Serious Organised Crime Agency (Soca), said: "The scale of this joint operation by law enforcement agencies from so many countries is an indication of how prolific we think this network was.
"Today's (Tuesday's) arrests will have dealt a major blow to an organised criminal business suspected of supplying drugs and guns to gangs in cities across the UK and Europe. It highlights Soca's role in co-ordinating complex investigations into organised crime, which always has an international dimension.
"We also believe this network has been offering a global investment service, ploughing hundreds of millions of pounds of dirty cash into offshore accounts, companies, and property on behalf of criminals. A financial investigation is already under way."