A man has been rescued by police after being held hostage for eight days by kidnappers in Liverpool.
The man, 42, believed to have been abducted in a dispute between drug gangs, went missing while on his way to work by car in London on 13 March.
Police raided an address in Liverpool on Wednesday night and freed the man.
Addresses in Knowsley, Merseyside, Brentwood, Essex, and Denham, Bucks, are being searched. Eleven men and one woman have been arrested.
Scotland Yard said it was the longest-running kidnap case it had ever investigated.
During the investigation officers have seized about nine kilograms of cocaine, worth £250,000, amphetamines, two firearms and £200,000 in cash.
Det Ch Supt Sharon Kerr, from the Specialist Crime Directorate, said: "Not only have we saved this man's life, we have got a lot of intelligence and ripped the heart out of one of the most significant criminal networks operating in this country."
The man, who was kidnapped on his way to work at 0500 GMT, is being treated for injuries to his face and upper body, which are not thought to be life-threatening.
Scotland Yard said they had worked alongside officers from other forces and acted to free the man after "several tense days of building up intelligence".
Det Ch Supt Kerr said: "Officers from the Kidnap Unit are used to working in some of the toughest policing conditions, with investigations invariably involving violent criminality.
"That makes the risks extremely high and the threat to life real and constant.
"We are rightly proud of our track record when dealing with kidnaps, but we never take it for granted and no matter the background of those involved we take our duty to preserve life extremely seriously."