When police tried to enter the nondescript terraced house in Green Lanes, north-east London, they soon realised it was no ordinary family home.
The front door was so well fortified the officers had to smash a hole in a wall, break down two heavy metal gates and knock through a triple-glazed window to get in.
Upstairs, they broke through a sound-proof, 4in-thick door and found a torture chamber. Two large black metal hooks had been screwed into the ceiling, and wired to the mains. Victims would be suspended and beaten between electric shocks.
They had made the mistake of crossing Abdullah Baybasin. Despite being wheelchair-bound since the mid-1980s, the 45-year-old father of one headed a Kurdish and Turkish crime syndicate and was considered to be one of Britain's most powerful gangsters.
Baybasin co-ordinated a massive drug-smuggling ring, ran extortion rackets and forced other criminals to pay him a "tax" for permission to operate. He is linked to more than a dozen brutal murders.
The gangster, known as "Uncle", will be sentenced next month, having been convicted of plotting to supply heroin. He pleaded guilty to conspiring to blackmail and pervert the course of justice. Ten other members of his gang have been jailed for between five and 16 years for offences including kidnap and supplying heroin.
Baybasin came to England from Turkey in 1997 to claim asylum. Although unable to walk since he was hit in the spine during a shoot-out in an Amsterdam bar, he managed to establish himself in north London and recruited young Kurds to form a gang called the bombacilars, the bombers. Armed members would force their way into shops and small businesses and demand money.
On one occasion, 20 of them, armed with samurai swords, metal bars, pool cues and a gun, forced their way into a Turkish café in Hackney, north-east London. One man had his index finger chopped off by the gang and shots were fired.
For years, Baybasin had ensured he was never in the same room as even the smallest quantity of drugs in case of a police raid. But in March 2001 he became too closely involved in a deal, and that began his downfall. Detectives hid a tiny video camera and microphones in the office behind a Green Lanes sports club from which Baybasin was operating. The watchers say it was like spying on scenes from The Godfather.
"People were clearly in awe of him," one says. "Baybasin would turn up two or three times a week. People would come and kiss his hand. When he spoke, it would be in a soft whisper so only the people closest to him could hear."
Their cameras recorded shopkeepers and local businessmen being brought into the room and beaten until they agreed to pay protection. "You could hear people being kicked and punched. The violence erupted out of nowhere."
Guns were distributed, petrol bombs were assembled and punishments for those who had refused to pay were discussed. Police had footage of one of the gang members being stripped and threatened with a machete over a breach of discipline. Fellow criminals did not escape Baybasin's attentions. Human traffickers had to pay £1,000 for each person smuggled. Pimps and drug dealers would also hand over money.
Much of their fear stemmed from Baybasin's family connections and the reputation of his elder brother, Huseyin, who is in prison in the Netherlands.
Better known as The Emperor, Huseyin began his criminal life selling black-market cigarettes in Istanbul. Then he moved into hashish trafficking, then heroin. As his business grew and the money began to roll in, Huseyin bought business and property interests in Britain, including a seaside hotel in Brighton and foreign exchange bureaus.
He also owned dozens of beach resorts, electrical shops and car-hire businesses along Turkey's southern coast.
In 1984, he was arrested in London with a load of heroin and sentenced to 12 years. But after just three years he was transferred to Turkey and immediately released, prompting allegations of high-level Turkish corruption.
In 2001, in Amsterdam, "the Emperor" was convicted on charges of conspiracy to murder, kidnapping and drug smuggling and sentenced to 20 years, later increased to life. Abdullah moved in.
Like many senior gangsters, Abdullah was also an informant for Customs and Excise, which allowed him to sabotage rivals and operate with protection. This fell apart when the now-defunct National Crime Squad began investigating.
By the time of his arrest, police estimate he was controlling 90 per cent of Britain's heroin trade as well as earning hundreds of thousands of pounds from blackmail and extortion.
Angry members of the Green Lanes community got together and decided to fight back. In November 2002 a battle broke out between 40 men armed with guns, knives and baseball bats outside a café, the Dostlar Social Club, in Green Lanes, owned by a relative of Baybasin. Twenty men were injured and an innocent man, Alisan Dogan, a 43-year-old Kurdish cleaner, was knifed to death.
A Met unit set up to tackle organised crime in the Turkish community remains active. The street price of heroin is at an all-time low, proving supplies are plentiful and Turkish crime is as strong as ever.
Outside the Kelkitt café in Green Lanes local businessmen were not breaking out the champagne. "The Baybasins are a huge clan and they are everywhere," said one. "Abdullah has many relatives in London. I don't believe we've heard the last of the Baybasins."