As students and other middle-class demonstrators assemble in Istanbul, Turkey, to protest the government policies of Prime Minister Recep Tayyip Erdogan, 1,500 miles away in London, England, Turks of a completely different nature are engaged in a violent turf war over the spoils of organized crime.

Three Turkish men have been sentenced to prison in connection with the February 2012 assassination of Ali Armagan, the 32-year-old boss of a London Turkish drug gang -- the bloody culmination of a four-year street war between two rival crews that claimed five lives as well as more than two-dozen stabbings, shootings, arson attacks and other incidents.

The three convicted men -- Suleyman Tonbul, 54; his son Hasan, 25, both of Edmonton; and Mehmet Senel, 23, from Tottenham -- were convicted on charges of conspiracy to cause grievous bodily harm. Suleyman Tonbul received eight years in prison, Hasan got 11 years and Senel will serve 10 years.

“The killing [of Armagan] took place against the background of a long-running feud between two Turkish drug gangs operating in north London,” Prosecutor William Emlyn Jones told the Old Bailey court.

“On any view, this was a particularly bloodthirsty feud.” Armagan and his brother Kemal were leaders of a London gang called Bombacilar ('Bombers' in Turkish), also known as the ‘Hackney Turks,’ referring to their neighborhood base in North London

Armagan's principal enemy, Kemal Eren, led the ‘Tottenham Turks’ of North London. He is believed to be responsible for the shooting of Armagan, according to the Daily Mail, but he escaped British justice by fleeing to his native Turkey.

In December 2012, 10 months after the Armagan killing, Kemal Eren himself was shot and seriously wounded in a retaliatory attack in Elbistan in the heavily Kurdish southeastern part of Turkey. Zafer Eren, who had links to the Tottenham Turks, was killed just two months ago in Southgate, North London, no doubt to compensate for the failure to dispatch Kemal to the grave.

Kemal Eren’s nickname is “Parmaksiz” which translates to "No Fingers" given his lack of some digits. Eren is now alive, but reported paralyzed and wheelchair-bound. While Britain has an extradition relationship with Turkey, it is unclear if Eren will be brought back to the UK for trial.

Interestingly, BBC reported, many members of both the Tottenham and Hackney gangs are actually Kurdish, not Turkish, and some belong to the Alevi faith, not to mainstream Islam.

Israfil Erbil, the lead of the Alevi Cultural Centre in Dalston, East London, tried to explain why some Kurdish/Turkish immigrants in Britain turned to a life of crime.

"Turkish people who immigrated into the UK in the 1980s have neglected their children while they were struggling to survive in this new country,” he told BBC. ”This neglect created a lack of identity within the second generation. This lack of belonging was fulfilled by gangs. The youths who take part in these gangs want to feel they belong somewhere. Do we need an innocent [British] person to be killed before this [violence] is stopped? Now is the time. Enough is enough."

The cycle of violence between these gangs will likely continue, police fear.

"It's difficult to stop because if someone wants to seek revenge, they will do it and, as the Armagan case shows, it only takes a few minutes for them to succeed," Detective Chief Inspector Kenny McDonald of London police told BBC.

McDonald added that the Turkish community are “vastly law-abiding and bring a great deal to [London], and these individuals are not a true reflection of the community at large. They are just criminals.”

Some local politicians are also concerned by the violence perpetrated by rival Turkish gangs in England.

“In 2009 I called for there to be investment specifically in tackling the blight of Turkish gangs and the need to recruit more Turkish speaking officers,” said David Lammy, the Labour MP for Tottenham.

“From what I hear locally, this hasn't taken place and it now urgently needs to. It is unacceptable that a handful of thugs are being allowed to damage the name of London's Turkish-speaking community and it is even more unacceptable that the law-abiding majority are being left to live in fear of what will become of them and their children."

Caught in the middle of this violent feud between drug gangs are law-abiding Turkish and Kurds in London.

“People are quite scared. It’s really affected everyone,”  Sarah Karakus, an activist who lives in North London, told the Standard newspaper.

“Because it’s a gang thing and people are worried about repercussions… Parents are not letting their children out at night at the moment because there is a kind of alarm. Families follow their kids to see if they are really going to school or going somewhere else.”

Britain’s Turkish-Kurdish criminal gangs are a relatively recent entry into the UK’s long and bloody history of organized crime, however, they are known to be deeply involved in the heroin trade.

A former North London Turkish gang-member named Suleyman Ergun claimed to Vice magazine that he was at one time one of the world’s largest heroin dealers, flooding both the UK and Europe with the drug for a period of five years. Before his incarceration, he was a millionaire many times over.

“Me, my former brother-in-law Yilmaz Kaya, and an Istanbul babas [godfather] named the Vulcan founded the Turkish Connection that’s a network that smuggles heroin from Afghanistan across Turkey into Europe,” Ergun said.

“Up until the early 1990s, Turks had been bringing it in piecemeal. An immigrant would bring in ten [kilos], sell it, buy a shop in Green Lane [a street in North London] and pack it in. We were the first to start bringing it in 100-kilo loads. Stack ’em high, sell ’em cheap.”

According to the London Street Gangs Blog, Turkish and Kurdish criminals have been operating in North London since the late 1970s and are believed to have imported thousands of kilos of heroin into the UK.

The Turk-Kurd gangs have reported made links with long established British crime organizations including Irish, Chinese and other groups.

The Kurdish-Turkish population in London is currently estimated at about 220,000. The community traces its origins to the arrival of thousands of Turkish Cypriots in the late 1940s, followed the later influxes of mainland Turks and later, Kurds.