Turkey has been shaken by the most extensive and sensational corruption investigations of its recent history that have led to dozens of detentions - from renowned business people to senior bureaucrats and sons of ministers.
There is a consensus in Turkey that the graft crackdown is linked to the recent tensions between the United States-based Turkish cleric Fethullah Gulen's movement and Prime Minister Recep Tayyip Erdogan's ruling Justice and Development Party (AKP) that, many analysts say, used to be allies in the past in their struggle against Turkey's politically dominant military.
Erdogan was furious in his first reactions to the crackdown. He called the probe a "dirty operation" to smear his administration and undermine the country's progress.
The prime minister said that those behind the investigations were trying to form a "state within a state" in an apparent reference to the movement of Gulen, whose followers are apparently highly influential in Turkey's police forces and judiciary.
Corruption in state tenders, money laundering, bribery, gold smuggling and distribution of prime land among favourites are among the accusations put on the suspects, sources at Istanbul chief prosecutor's office told Turkish media. Formal criminal charges are going to be revealed after the prosecutor's office announces the actual bills of indictment for the three simultaneous investigations it has been carrying out.
Those detained include the sons of Interior Minister Muammer Guler, Economy Minister Zafer Caglayan and Environment Minister Erdogan Bayraktar. Various well-known businessmen were also detained, including Suleyman Aslan, the chief executive of Turkish state bank Halkbank, and Ali Agaoglu, a construction tycoon, as well as Mustafa Demirand, the mayor of Istanbul district Fatih. Some of these prominent people were arrested while others were released by court order, all pending trial.
Dozens of police officers removed
The government's almost immediate reaction to the blow was to initiate a country-wide comprehensive overhaul in the Turkish Police Force on Wednesday, only one day after the raids over the probe.
Consequently, dozens of senior police officers, including the Istanbul police chief, have been removed from their posts and assigned to passive positions over the government's claims of "abuse of office". The move apparently aims at evacuation of certain security personnel that Ankara believes are linked to the investigations.
Anti-government demonstrations have been organised in various cities of Turkey following the probe, particularly in Istanbul and Ankara.
Istanbul police have banned media members from entering the force's buildings and accredited journalists were asked to hand over their entry cards.
The Turkish media environment is highly polarised over the issue with media organisations taking sides according to their affiliations. Recently, Nazli Ilicak, a pro-government columnist and former politician, has been fired from Sabah, a pro-AKP newspaper. Only days before she was sacked, she took an unusual stance and said that the ministers involved with the probes should resign.
Ilicak said in a recent statement that it would go against her conscience to say there was no political pressure on the media. "I am convinced that pressure has been used as a method against political criticism. This is how the climate feels," she said.
In March, veteran journalist Hasan Cemal was sacked by Milliyet newspaper in a similar case after Erdogan publicly criticised him over an article on the Kurdish question.
Existence in state
Fethullah Gulen, 72, has been living in self-imposed exile in the US since 1999, reportedly, for health reasons and to escape from various charges in Turkey.
His movement is famous for its success in the area of education with tens of schools spread across the globe. It is widely believed that that the organisation encourages graduates to take positions in Turkish state institutions.
The cleric himself accepts that his sympathisers are positioned in the state and he encourages them to take part in various institutions, but refutes the claims that he organises his followers for this cause.
"I am essentially a child of Anatolia … For the sake of the values of my country it is normal [to] tell [my sympathisers] to become police officers, diplomats, soldiers or jurists," he said in one of his regular sermons.
In the past, various people who conducted research on the Gulen movement's existence in state institutions have stood trials and sentenced to prison time for unrelated charges.
Journalist Ahmet Sik served one year in prison until March 2012 in the so-called Eregenekon case looking into an alleged clandestine organisation in the Turkish state. Ex-police chief Hanefi Avci has been in prison since 2010 over the so-called OdaTV case that charges the media organisation in question with being the "media arm" of Ergenekon. Both Sik and Avci have written books on the Gulen movement.
Many believe that such arrests have been made by members of the movement in the Turkish judiciary and police.
"To a large extent, it is possible to say that the [Turkish] public thinks that Avci had been silenced through investigations and trials by exactly the same people against whom he was fighting," writes Rusen Cakir, a Turkish journalist and columnist who has also worked on the Gulen movement, in a research article from October.
Cases such as Ergenekon and Sledgehammer targeted former and active high-level military officers as well as other anti-AKP establishments such as media and non-governmental organisations over plans to overthrow the government. The cases are seen as one of the main areas of cooperation between the government and the Gulen movement.
According to Ahmet Sik, in late-2000s, Erdogan saw that he could not avoid being a target of Turkey's army, the traditional defender of Turkey's secular state, although he was willing to share the power with the generals.
"He saw the danger of a coup and made the Gulen movement a partner in power instead [of the military] in order to carry out the Ergenekon process," he said in a recent interview.
Etyen Mahcupyan, a columnist at the Gulen movement's flagship Zaman newspaper, told Al Jazeera that Gulen sympathisers are a "large and transitive" group in the state, adding that there are others who are not directly involved with the movement but act in line with it in order to protect their bureaucratic careers.
"The government knows the central cadre of the movement in state institutions. It is not possible to intervene in the ones in the judiciary but they can be passivised in time through the Supreme Board of Prosecutors and Judges (the institution responsible for assignment of prosecutors and judges). The ones in the police force can be pulled out from active duties quickly," Mahcupyan said.
The Gulen movement backed the AKP in its 11-year rule up until recently. Today's bitter row that has escalated gradually in the last couple of years is another serious test for the AKP, following last summer's country-wide anti-government protests, and ahead of a series of elections starting in March 2014.
Analysts say that the tensions between the movement and the government stem from a variety of factors, with the two sides falling apart on several foreign policy issues and Turkey's Kurdish question.
Sources close to Gulen say that the "first crack" in the AKP-Gulen alliance was the Mavi Marmara incident in 2010 when Israeli troops attacked a flotilla boat heading from Turkey to Gaza, killing eight Turkish and one American activist. Relations between the two countries still remain in crisis.
"[Gulen's followers] never approved the role the government tried to attain in the Middle East, or approved of its policy in Syria, which made everything worse, or its attitude in the Mavi Marmara crisis with Israel," Ali Bulac, a conservative writer who supports Gulen, recently told The New York Times.
Mahcupyan told Al Jazeera that that there was an "apparent" difference between the sides in their approach to the Kurdish issue, specifically on the direct talks the Turkish intelligence has been holding with Abdullah Ocalan, the leader of the Kurdistan Workers Party (PKK).
"The government believes that direct talks with Ocalan and the PKK are the way forward for a settlement. In contrast, the Gulen movement is against addressing the PKK directly, but it does not oppose giving [Turkey's Kurds] their cultural rights," Mahcupyan says.
PKK is an outlawed Kurdish armed group that has been fighting against Turkey for around 30 years. Its demands gradually transformed from Kurdish independence to autonomy and, now, to a fully democratised Turkey for all.
Mahcupyan notes that members of the Gulen movement tackled the PKK in southeastern Turkey for years and its followers in the judiciary carried out the cases against the Union of Communities in Kurdistan (Koma Civakên Kurdistan in Kurdish or KCK), the alleged umbrella organisation of the PKK along with other Kurdish groups in the wider region.
Gradual poisoning of relations
There were also a series of incidents that apparently poisoned the relations and ended up with two sides burning bridges.
In February 2012, a prosecutor called in five active and former senior intelligence officers, including Hakan Fidan, the undersecretary who heads the National Intelligence Organization (MIT), for interrogation as "suspects". They were asked to respond to charges that they had illegal contact with the PKK, referring to a series of talks between them and several senior PKK members in the Norwegian capital of Oslo among other charges.
It was even a complaint, sometimes implicit, sometimes explicit, that the Gulen movement pressured policies on the government through their veins in the state.
Erdogan publicly declared that he personally assigned the intelligence officials in question to the talks the Turkish judiciary was charging them for. His government soon made legal amendments making prime minister approval mandatory to investigate intelligence members.
Many analysts, and apparently the government, believes that Gulen sympathisers in the judiciary were behind the move.
Rusen Cakir writes on the issue: "One of the most significant differences of this crisis [compared to others] has been that the AKP did not refute the claims about the Gulen movement's organisations within the government, which has been on the country's agenda for a long time. It was even a complaint, sometimes implicit, sometimes explicit, that the Gulen movement pressured policies on the government through their veins in the state."
In November, Turkish daily Taraf published a leaked 2004 national security document signed by AKP government ministers, including the prime minister, revealing a planned action against the Gulen movement. It advised the government to adopt measures that would impose harsh penalties on Gulen-affiliated institutions.
The last source of strain was the government's plans to abolish private prep schools that prepare students for various exams in the Turkish educational system. Gulen owns a large network of such schools, a major source of revenues and human resources.
Mahcupyan thinks that "a soft rapprochement" between the two fronts does not seem possible at this point. But he also notes that the supporters of both sides are highly irritated by the current situation.
"Most probably they will continue to clash until the elections [in March] with the aim to influence the results. The corrosive nature of the process might force the sides to stop. Or, if none backs down, third parties might take initiatives for mediation," Mahcupyan said.
Ahmet Sik believes a war between the two sides would be "a nuclear war" without any potential victors.
"I think both sides have enough documents and knowledge about each other to finish one another," he recently told Turkish media.
Follow Umut Uras on Twitter: @Thriceee